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How image orientation influences perception

How image orientation influences perception



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Im a painter for many years. When I paint, I usually walk around and look at my painting for many hours. When painting session is long, it harder and harder to maintain a "fresh look".

By fresh look; I mean state of mind (perception) when I am as objective about my work as possible. The longer the session continues and painting is changed; its harder for me to be objective about it.

To be objective and fresh, artists would take many 5-min breaks in one painting session. I used to do that too, until I learned a "strange trick" from my friend.

Whole trick is to take your painting and just rotate it about 90 or 180 degrees for a moment and look at it. Surprisingly, this gives a fresh (somehow new) perspective at painting.

I would like to ask; why is that?

It seems to me, that somehow brain filters out many informations about images that it knows. When I rotate my image; it is recognized as different (not "known").

Any research on described phenomenon?


No life can emerge in chaos - for life to emerge the environment has to be orderly. Organisms have to adapt to their environment, meaning optimise (or satisfice) output in light of input. In a patternless environment, there is no chance doing so.

Our brain evolved in light of this - we constantly learn and update what the "norm" is - let it be there's light if it's day or the hair colour of your partner. Equally, the brain constantly compares stimuli to the norm - if it's all good, no action needed, but a deviation from the norm shall raise an alarm bell.

Thus, we are 'programmed' to ignore what's normal, and be alert to the abnormal. Perhaps the most famous example of it is the sound of mechanical clock, which is simply not perceived once we spend enough time in the room it is in.

In your specific case, seeing the same image for a prolong time results in it becoming a norm in our brain, resulting in reduced brain activity.


It is difficult to examine this phenomenon because we would have to define what it means to have a "fresh look" and how we could measure it. It is an interesting observation though. Here are a few possibilities for how we might interpret what's going on here, with some references to related cognitive science research.

One obvious point is that we recognise things more slowly when they are upside down. This is particularly well known in face recognition, but there are also (smaller) inversion effects in other types of stimuli such as scenes. This is often taken as evidence that when we encode or recognise something, we are not just remembering the pieces separately but are doing some sort of "holistic" processing which fits them together. In this case, you could say that when you turn the picture you take longer to recognise it, or that you see it as novel, and that makes you view it in a "fresh" way. https://www.researchgate.net/profile/Jesse_Husk/publication/5857415_Inverting_houses_and_textures_Investigating_the_characteristics_of_learned_inversion_effects/links/55dcbc1b08ae83e420ee5038.pdf

A related point is that objects often have a "canonical orientation" which we are most used to seeing them from. This has been a point of interest for models of object recognition, which often assumed that our representation is "view independent". So if you are painting objects, it certainly would be harder to process if you rotate them from the canonical. http://s3.amazonaws.com/academia.edu.documents/30745263/pdf699.pdf?AWSAccessKeyId=AKIAJ56TQJRTWSMTNPEA&Expires=1472559612&Signature=yDh4VqjQ%2Bsg1ibIebSzKt4fMvmM%3D&response-content-disposition=inline%3B%20filename%3DOrientation_dependence_in_the_recognitio.pdf

As we might expect from the above, viewing something from a different orientation does actually change the things that we pay attention to and look at. For example, people make frequent horizontal eye movements when looking at landscapes, but if you rotate the image they seem to make a different pattern and may be drawn to different things. http://supersaturated.com/papers/pdfs/horizonSaccade.pdf

http://jov.arvojournals.org/article.aspx?articleid=2158151


Mass Communication Talk

Q.5:Define perception and identify some psychological factors that influence perception. Also highlight the role of perception in mass communication.

Perception, Psychological Factors that Influence Perception in Mass Communication

Much of the research showing that perception is influenced by assumptions has come from a group of researchers working at one time or another at Princeton University. These researchers, who have included Adelbert Ames, Jr., Hadley Cantril, Edward Engels, Albert Hastorf, William H. Ittelson, Franklin p. Kilpatrick, and Hans Tech, have presented what has been called the transactional view of perception. The concept is abstract and somewhat philosophical, but essentially it means that both the perceiver and the world are active participants in an act of perception (Tech & MacLean, 1962).

The transactional thinkers have developed a number of convincing demon­strations that perception is based on assumptions. One of the most striking, invented by Adelbert Ames, Jr., is called the monocular distorted room. This room is constructed so that the rear wall is a trapezoid, with the vertical distance up and down the left edge of the wall longer than the vertical distance up and down the right edge of the wall. The rear wall is positioned at an angle so that the left edge is farther back than the right edge. This angle is carefully selected so that the room will appear to be an ordinary rectangular room to an observer looking through a small hole at the front of the room. If two people walk into the room and stand in the rear corners, something interesting happens. The one on the right appears to a viewer looking through the hole to be very large because he or she is closer to the viewer and fills most of the distance from the floor to the ceiling. The one on the left appears to be very small because he or she is farther away and fills less of the distance from the floor to the ceiling. This illusion occurs because the mind of the viewer is assuming that the rear wall is parallel to the front wall of the room. This assumption is based on prior experience with other rooms that looked similar. The illusion is so strong that if the two people in the corners switch places, one will appear to grow larger and the other will appear to get smaller, right before the viewer’s eye.

Psychological Factors that Influence Perception:

Cultural Expectations and Perception

Some of the most striking evidence for the influence of cultural expectations on perception comes from research on binocular rivalry (Bagby, 1957). It is possible to construct a device that has two eyepieces like a pair of binoculars, but can be used to present a different picture to each eye. When this is done, people seldom see both pictures. They more often see one picture and not the other or one picture and then the other. Sometimes they see a mixture of some elements of each picture, but this usually occurs after seeing one picture alone first. Bagby used this instrument to investigate the effect of cultural background on perception.

Subjects were 12 Americans (6 males and 6 females) and 12 Mexicans (6 males and 6 females). Except for one matched pair made up of a person from each country, the subjects had not traveled outside their own country. Bagby prepared ten pairs of photographic slides, each pair containing a picture from the American culture and a picture from the Mexican culture. One pair, for instance, showed a baseball scene and a bullfight scene. Subjects were exposed to each slide for 60 seconds and asked to describe what they saw. The assignment of the Mexican or the American picture to the left or right eye was randomized to eliminatethe effect of eye dominance. The first 15 seconds of viewing for each slide were scored for which scene was dominant—the Mexican or

TABLE :Perceptual predominance in 10 pairs of pictures for Mexican and American subjects

Trials Where

source From J. W. Baby, “A Cross-cultural Study of Perceptual Predominance in Binocular Rivalry,” Journal of Abnormal and Social Psychology 54 (1957): 333. Copyright © 1957 by the American Psychological Association, Reprinted by permission, the American. Dominance was determined by the scene that was reported first or was reported as showing up for the longest period of time. The results (Table 4.1) indicate a strong tendency for subjects to see the scenes from their own culture rather than the scenes from an unfamiliar culture.

Motivation and Perception:

One of a number of experiments that shows the effect of motivation on percep­tion was done by McClelland and Atkinson (1948). The type of motivation being investigated was hunger. Subjects were Navy men waiting for admission to a submarine training school. One group had gone 16 hours without food, a second 4 hours without food, and the third 1 hour without food. All subjects were told they were participating in a test of their ability to respond to visual stimulation at very low levels. The men went through 12 trials in which a picture was supposedly projected, but actually nothing was projected at all. To make this realistic, during the instructions they were shown a picture of a car and then the illumination was turned down until the car was only faintly visible. In some of the trials subjects were given clues such as: “Three objects on a table. What are they?”

The results (Table 4.2) showed that the frequency of food-related responses increased reliably as the hours of food deprivation increased. Furthermore, in another phase of the experiment food-related objects were judged larger than neutral objects by hungry subjects but not by subjects who had recently eaten.

Mood and Perception:

An experiment using hypnosis demonstrated that mood has an effect on percep­tion. Leuba and Lucas (1945) hypnotized subjects, suggested to them that they were experiencing a certain mood, and then asked them to tell what they saw

in a picture. Each subject was put in a happy mood and then shown six pictures. Then the subject was told to forget the pictures and what had been said about them and was put in a critical mood and again shown the same six pictures. Finally, the subject was given the same treatment once more except that the suggested mood was anxious. The descriptions of the pictures were drastically different depending on the mood the person was in. They differed not only in the train of thought the pictures suggested but also in the details noticed.

One picture showed some young people digging in a swampy area. Here is one subject’s description of that picture while in a happy mood:

It looks like fun reminds me of summer. That’s what life is for working out in the open, really living—digging in the dirt, planting, watching things grow.

Here is the same subject describing the same picture while in a critical mood:

Pretty horrible land. There ought to be something more useful for kids of that age to do instead of digging in that stuff. It’s filthy and dirty and good for nothing.

Here is the same subject describing the same picture while in an anxious mood:

They’re going to get hurt or cut. There should be someone older there who knows what to do in case of an accident. I wonder how deep the water is.

Attitude and Perception:

The effects of attitude on perception were documented in a study of perception of a football game by Hastorf and Cantrii (1954). The 1951 football clash between Dartmouth and Princeton was an exciting and controversial one. Princeton’s star player Dick Kazmaier was taken out of the game in the second quarter with a broken nose. In the third quarter, a Dartmouth player received a broken leg. Discussion of the game continued for weeks, with editorials in the two campus newspapers charging the other school with rough play. Hastorf and Cantrii took advantage of this situation to conduct a study in perception. They showed a film of the game to two groups: two fraternities at Dartmouth and two undergraduate clubs at Princeton. Students from both schools saw about the same number of infractions by the Princeton team. But Princeton students saw an average of 9.8 infractions by the Dartmouth team, while Dartmouth students saw an average of 4.3 infractions by the Dartmouth team. That is, the Princeton students saw more than twice as many violations by the Dartmouth team as did the Dartmouth students. Hastorf and Cantrii state, “It seems clear that the ‘game’ actually was many different games and that each version of the events that transpired was just as ‘real’ to a particular person as other versions were to other people” (p. 132).

PERCEPTION AND MASS COMMUNICATION:

So far this discussion of research has shown that perception in general is influenced by assumptions (often unconscious), cultural expectations, needs, moods, and attitudes. The same kinds of forces are at work when people respond to mass communication messages, as the following cases show.

U.S. Army TV Spots:

Mass media messages are often misunderstood. Keck and Mueller (1994) con ducted a study of U.S. Army television commercials to see whether viewers were perceiving the intended messages, and if not, what messages they were perceiving.

The study focused on two 30-second TV spots. One spot, titled “Dear Dad,” was intended to show that Army service builds personal growth, maturation, and character development, and to portray the Army as exciting, adventurous, and challenging. The second spot, titled “Basic Excellence,” portrayed basic training as a means to discover one’s ability and to overcome personal fears and inhibi­tions. The target audience for the ads was white males between 18 and 24 years of age.

A group of 396 respondents drawn from the target audience was then shown the spots and asked to fill out a questionnaire. Results showed that some of the intended messages were being perceived by the audience. For instance, 61 percent of the respondents agreed that the activities portrayed in “Basic Excellence” were exciting and challenging. Also, 68 percent agreed that a senseof personal accomplishment could be gained from engaging in the activities highlighted in the spot.

But large percentages also perceived unintended messages. For instance, 39 percent perceived that the drill sergeant was not portrayed realistically in the advertisement. And 66 percent perceived that engaging in the activities portrayed in the commercial would not lead to a good job.

There were also systematic relationships between misperceiving the ads and various characteristics of the audience. For instance, 54 percent of the black respondents felt that the drill sergeant in “Basic Excellence” was accurately portrayed, while only 26 percent of the white respondents and 32 percent of the Hispanic and Asian respondents felt that he was.

In addition, 84 percent of those with no college education thought that “Dear Dad” was a true representation of life in the Army, while only 27 percent of those with some college and 9 percent of the college grads felt that it was.

Antiprejudice Cartoons

Satire is a familiar journalistic device. It has been used in works ranging from Jonathan Swift’s Gulliver’s Travels to Garry Trudeau’s “Doonesbury” comic strip. But how is satire perceived?

The American Jewish Committee was interested in studying the effects of satire in reducing prejudice. It sponsored a study by Eunice Cooper and Marie Jahoda (1947) that investigated the effects of antiprejudice cartoons. The cartoons featured an exaggerated figure named “Mr. Biggott,” who appeared in situations designed to make prejudice appear ridiculous. For instance, one cartoon showed Mr. Biggott lying in a hospital bed and dying. He is saying to the doctor, “In case I should need a transfusion, doctor, I want to make certain I don’t get anything but blue, sixth-generation American blood!” The intention was that people looking at the cartoon would see how ridiculous prejudice is and would lessen their own feelings of prejudice.

Cooper and Jahoda tested the cartoons on 160 white, non-Jewish working- class men. About two-thirds of the sample misunderstood the cartoons. Some said the purpose of the cartoons was to legitimize prejudice. These people explained that the cartoons showed that other people had attitudes of prejudice, so the viewer should feel free to have those attitudes also. The cartoons were most likely to be understood by respondents low in prejudice and most likely to be misunderstood by respondents high in prejudice. Cooper and Jahoda suggested that fear of disapproval by a social group was one of the factors leading to this evasion of propaganda. They argued that accepting the antipreju­dice message threatened the individual’s security in groups the individual valued.

This study suggests that making fun of prejudice is not an effective way of reducing it. People tend to view satiric cartoons differently, depending on their own attitudes. Both prejudiced and unprejudiced people tended to see elements in the cartoons that confirmed their existing attitudes.

PERCEPTION OF PICTURES:

The mass media frequently employ pictures as part of messages. What do we know about how people interpret these pictures? Scott (1994) has argued that we need a theory of visual rhetoric to help us understand how people process pictures, and has offered some thoughts to move us forward in developing such a theory.

Scott suggests that much research on images in advertising has dealt with pictures either as transparent representations of reality or as conveyors of an emotional appeal. She argues for a third possibility—that pictures can act as symbols and can be used to construct rhetorical arguments. She states that visual elements are capable of representing concepts, abstractions, actions, metaphors, and modifiers, and that they can be assembled into complex arguments. Further­more, this conceptualization of images means that pictures need to be processed cognitively like other forms of information.

Scott’s article brings out three ways of thinking about pictures in the mass media—as transparent representations of reality, as conveyors of affective or emotional appeal, and as complex combinations of symbols put together to make up rhetorical arguments. Different types of pictures in the mass media may be used in these three ways to varying degrees. For instance, news photos may be higher in use as transparent representations of reality than pictures in advertisements, while pictures in advertisements may be used as parts of rhetorical arguments more than news photos. Both types of images may be at times high in conveying affective or emotional appeal (see Table 4.3).

To illustrate the rhetorical use of visual images, Scott analyzes a Clinique ad that shows tubes of lipstick and makeup immersed in a glass of soda water garnished with a slice of lime.

The image is not intended to be taken literally—the message is not that the lipstick and makeup tubes are waterproof, for instance. Scott says we can restate the message of the image in verbal terms in this way “Clinique’s new summer line of makeup is as refreshing as a tall glass of soda with a twist.” The ad is essentially a visual simile. It is an example of a visual trope, an argument presented in a figurative form in order to break through a viewer’s skepticism, boredom, or resistance.

Perceiving the Clinique ad correctly requires some rather complex informa­tion processing on the part of the perceiver. The viewer must compare two rather dissimilar things—soda water and cosmetics—and deduce what they have in common. Of several things they have in common, the correct one must be selected (“refreshing” but not “tasteless”) in order to arrive at the simile.


How image orientation influences perception - Psychology

While our sensory receptors are constantly collecting information from the environment, it is ultimately how we interpret that information that affects how we interact with the world. Perception refers to the way sensory information is organized, interpreted, and consciously experienced. Perception involves both bottom-up and top-down processing. Bottom-up processing refers to the fact that perceptions are built from sensory input. On the other hand, how we interpret those sensations is influenced by our available knowledge, our experiences, and our thoughts. This is called top-down processing.

One way to think of this concept is that sensation is a physical process, whereas perception is psychological. For example, upon walking into a kitchen and smelling the scent of baking cinnamon rolls, the sensation is the scent receptors detecting the odor of cinnamon, but the perception may be “Mmm, this smells like the bread Grandma used to bake when the family gathered for holidays.”

Although our perceptions are built from sensations, not all sensations result in perception. In fact, we often don’t perceive stimuli that remain relatively constant over prolonged periods of time. This is known as sensory adaptation. Imagine entering a classroom with an old analog clock. Upon first entering the room, you can hear the ticking of the clock as you begin to engage in conversation with classmates or listen to your professor greet the class, you are no longer aware of the ticking. The clock is still ticking, and that information is still affecting sensory receptors of the auditory system. The fact that you no longer perceive the sound demonstrates sensory adaptation and shows that while closely associated, sensation and perception are different.

There is another factor that affects sensation and perception: attention. Attention plays a significant role in determining what is sensed versus what is perceived. Imagine you are at a party full of music, chatter, and laughter. You get involved in an interesting conversation with a friend, and you tune out all the background noise. If someone interrupted you to ask what song had just finished playing, you would probably be unable to answer that question.

Link to Learning

See for yourself how inattentional blindness works by watching this selective attention test from Simons and Chabris (1999):

One of the most interesting demonstrations of how important attention is in determining our perception of the environment occurred in a famous study conducted by Daniel Simons and Christopher Chabris (1999). In this study, participants watched a video of people dressed in black and white passing basketballs. Participants were asked to count the number of times the team in white passed the ball. During the video, a person dressed in a black gorilla costume walks among the two teams. You would think that someone would notice the gorilla, right? Nearly half of the people who watched the video didn’t notice the gorilla at all, despite the fact that he was clearly visible for nine seconds. Because participants were so focused on the number of times the white team was passing the ball, they completely tuned out other visual information. Failure to notice something that is completely visible because of a lack of attention is called inattentional blindness.

In a similar experiment, researchers tested inattentional blindness by asking participants to observe images moving across a computer screen. They were instructed to focus on either white or black objects, disregarding the other color. When a red cross passed across the screen, about one third of subjects did not notice it (Figure 1) (Most, Simons, Scholl, & Chabris, 2000).

Link to Learning

Read more on inattentional blindness though this link to the Noba Project website.

Figure 1. Nearly one third of participants in a study did not notice that a red cross passed on the screen because their attention was focused on the black or white figures. (credit: Cory Zanker)

Motivation can also affect perception. Have you ever been expecting a really important phone call and, while taking a shower, you think you hear the phone ringing, only to discover that it is not? If so, then you have experienced how motivation to detect a meaningful stimulus can shift our ability to discriminate between a true sensory stimulus and background noise. The ability to identify a stimulus when it is embedded in a distracting background is called signal detection theory. This might also explain why a mother is awakened by a quiet murmur from her baby but not by other sounds that occur while she is asleep. Signal detection theory has practical applications, such as increasing air traffic controller accuracy. Controllers need to be able to detect planes among many signals (blips) that appear on the radar screen and follow those planes as they move through the sky. In fact, the original work of the researcher who developed signal detection theory was focused on improving the sensitivity of air traffic controllers to plane blips (Swets, 1964).

Our perceptions can also be affected by our beliefs, values, prejudices, expectations, and life experiences. As you will see later in this chapter, individuals who are deprived of the experience of binocular vision during critical periods of development have trouble perceiving depth (Fawcett, Wang, & Birch, 2005). The shared experiences of people within a given cultural context can have pronounced effects on perception. For example, Marshall Segall, Donald Campbell, and Melville Herskovits (1963) published the results of a multinational study in which they demonstrated that individuals from Western cultures were more prone to experience certain types of visual illusions than individuals from non-Western cultures, and vice versa. One such illusion that Westerners were more likely to experience was the Müller-Lyer illusion (Figure 2): The lines appear to be different lengths, but they are actually the same length.

Figure 2. In the Müller-Lyer illusion, lines appear to be different lengths although they are identical. (a) Arrows at the ends of lines may make the line on the right appear longer, although the lines are the same length. (b) When applied to a three-dimensional image, the line on the right again may appear longer although both black lines are the same length.

These perceptual differences were consistent with differences in the types of environmental features experienced on a regular basis by people in a given cultural context. People in Western cultures, for example, have a perceptual context of buildings with straight lines, what Segall’s study called a carpentered world (Segall et al., 1966). In contrast, people from certain non-Western cultures with an uncarpentered view, such as the Zulu of South Africa, whose villages are made up of round huts arranged in circles, are less susceptible to this illusion (Segall et al., 1999). It is not just vision that is affected by cultural factors. Indeed, research has demonstrated that the ability to identify an odor, and rate its pleasantness and its intensity, varies cross-culturally (Ayabe-Kanamura, Saito, Distel, Martínez-Gómez, & Hudson, 1998).

Children described as thrill seekers are more likely to show taste preferences for intense sour flavors (Liem, Westerbeek, Wolterink, Kok, & de Graaf, 2004), which suggests that basic aspects of personality might affect perception. Furthermore, individuals who hold positive attitudes toward reduced-fat foods are more likely to rate foods labeled as reduced fat as tasting better than people who have less positive attitudes about these products (Aaron, Mela, & Evans, 1994).

Link to Learning

Review the differences between sensation and perception in this CrashCourse Psychology video.

Think It Over

1. Think about a time when you failed to notice something around you because your attention was focused elsewhere. If someone pointed it out, were you surprised that you hadn’t noticed it right away?


Relations among media influence, body image, eating concerns, and sexual orientation in men: A preliminary investigation

The current study explored the relation between sexual orientation, media persuasion, and eating and body image concerns among 78 college men (39 gay 39 straight). Participants completed measures of sexual orientation, eating disorder symptoms, appearance-related anxiety, perceived importance of physical attractiveness, perceptions of media influence, and media exposure. Gay men scored significantly higher on drive for thinness, body dissatisfaction, and body image-related anxiety than their straight counterparts. Additionally, perceptions of media influence were higher for gay men, and significantly mediated the relation between sexual orientation and eating and body image concerns. Sexual orientation also moderated the relation between perceived media influence and beliefs regarding the importance of physical attractiveness, as this relation was significant for gay men, but not straight men. The current findings suggest that gay men's increased vulnerability to media influence partially accounts for the relatively high rate of eating pathology observed in this population.


Influences on Top-Down Processing

According to Gregory (1970) different factors can influence top-down processing such as expectations, emotion, motivation and culture. This is known as perceptual set theory.

The context or situation in which we have previously perceived information can influence future expectations when receiving new information under similar circumstances.

To no surprise, previous experiences undoubtedly influence how new information is perceived as we, as humans, use the knowledge that we gained from prior events in order to construct expectations for perceiving new information.

Our brains are shaped by the external world and through context and experience our perception is also shaped by the external world.

For this reason, the influence of culture on shaping our perceptions cannot be ignored as culture creates differences in contexts and experiences that individuals draw from when perceiving new information (Deregowski, 1972).

Motivation can also influence top-down processing as you may be more motivated to perceive things depending on your needs and desires (Swets, 1964).

For example, let’s say you are waiting for a phone call that determines whether or not you were chosen for a recent position that you have interviewed for, and you hear the phone ring when you are taking a shower, when in fact, the phone never rang.

This is a perfect example of how motivation can influence perception because your need and desire for the phone to ring with that very important call is so strong that you are imagining hearing the phone ring when it is not in fact ringing at all.


Self-Concept, Self-Image and Self-Esteem

In this study note we explain the three related ideas of self-concept, self-image and self-esteem and how emotional development changes through the life stages.

Self-Concept

Self-concept is how someone sees themselves and the perception that they hold about their abilities. There are various factors that can affect self-concept, these include: age, sexual orientation, gender and religion. The self-concept is also made up of a combination of self-esteem and self-image.

Self-esteem refers to a person’s feelings of self-worth or the value that they place on themselves.

There are a number of characteristics of high and low self-esteem.

Characteristics of high self-esteem

  • Willing to try new things in their life
  • Can cope well under pressure
  • Emotionally stable and confident
  • Happy to share their ideas and experiences

Characteristics of low self-esteem

  • Feels worthless
  • Reluctant to try new things
  • Struggles in new or challenging circumstances
  • Do not value their own opinions and sensitive to the opinions of others

Factors affecting self esteem

  • Parents/carers teaching problem solving skills from a young age (so that a child feels a sense of achievement) can lead to a positive self-esteem.
  • Learning difficulties at school can lead to a child struggling to complete work or maintain friendships, which can lead to negative self-esteem.

Self-image refers to the way an individual sees themselves, both physically and mentally. An individual’s self-image is developed over time and influenced by the experiences they have encountered.

There are a number of characteristics of a positive and negative self-image.

Characteristics of a positive self-image

  • Feels confident
  • Compares themselves positively with peers
  • Content with how they look and has belief in their own ability
  • Positive feedback received from friends and family on looks and abilities

Characteristics of a negative self-image

  • Doubts own ability
  • Compares themselves negatively with peers and images on social media/TV/magazines
  • Received negative comments from friends and family on physical appearance or mental ability

Factors affecting self-image

  • Early childhood experiences and social interactions eg parents who pass positive comments to a child can help contribute to a positive self-image.
  • Life events or roles eg a child who is captain of the rugby team is more likely to have a positive self-image that a child who is bullied at school

Emotional Development through the life stages

During this stage, infants develop a sense of self and positive self-esteem through secure attachments with their caregivers. This starts with their basic needs being met as a baby.

Early Childhood

By the age of four, the child’s self-esteem develops further through the support they receive outside of the family. Being able to solve problems through puzzles will enhance self-esteem, as will involving the children in scenarios where their opinion is sought. Children who do not receive these experiences may develop low self-esteem.

Adolescence

Several factors affect self-esteem during adolescence. These can include stress within the home, or at school, or a combination of the two. Coupled with the changes that occur during puberty, these can all have an impact on self-image too.

Being bullied or not being accepted by your peers can have detrimental effects on a young person’s self-esteem and can feed into way they feel about themselves. This can lead to anxiety and depression and a sense of not belonging, all characteristics of having low self-worth. This can be intensified by peer pressure, the use of images in the media, social media and the increase in cyberbullying.

Self-esteem continues to develop through adulthood and an individual’s self-esteem may increase through the achievements they have made which, in turn, increases self-worth. During adulthood a person develops a real understanding of who they are and how to deal with situations more effectively and with more confidence.


The emotions we feel may shape what we see

Our emotional state in a given moment may influence what we see, according to findings published in Psychological Science, a journal of the Association for Psychological Science. In two experiments, researchers found that participants saw a neutral face as smiling more when it was paired with an unseen positive image.

The research shows that humans are active perceivers, say psychological scientist Erika Siegel of the University of California, San Francisco and her coauthors.

"We do not passively detect information in the world and then react to it -- we construct perceptions of the world as the architects of our own experience. Our affective feelings are a critical determinant of the experience we create," the researchers explain. "That is, we do not come to know the world through only our external senses -- we see the world differently when we feel pleasant or unpleasant."

In previous studies, Siegel and colleagues found that influencing people's emotional states outside of conscious awareness shifted their first impressions of neutral faces, making faces seem more or less likeable, trustworthy, and reliable. In this research, they wanted to see if changing people's emotional states outside awareness might actually change how they see the neutral faces.

Using a technique called continuous flash suppression, the researchers were able to present stimuli to participants without them knowing it. In one experiment, 43 participants had a series of flashing images, which alternated between a pixelated image and a neutral face, presented to their dominant eye. At the same time, a low-contrast image of a smiling, scowling, or neutral face was presented to their nondominant eye -- typically, this image will be suppressed by the stimulus presented to the dominant eye and participants will not consciously experience it.

At the end of each trial, a set of five faces appeared and participants picked the one that best matched the face they saw during the trial.

The face that was presented to participants' dominant eye was always neutral. But they tended to select faces that were smiling more as the best match if the image that was presented outside of their awareness showed a person who was smiling as opposed to neutral or scowling

In a second experiment, the researchers included an objective measure of awareness, asking participants to guess the orientation of the suppressed face. Those who correctly guessed the orientation at better than chance levels were not included in subsequent analyses. Again, the results indicated that unseen positive faces changed participants' perception of the visible neutral face.

Given that studies often show negative stimuli as having greater influence on behavior and decision making, the robust effect of positive faces in this research is intriguing and an interesting area for future exploration, the researchers note.

Siegel and colleagues add that their findings could have broad, real-world implications that extend from everyday social interactions to situations with more severe consequences, such as when judges or jury members have to evaluate whether a defendant is remorseful.

Ultimately, these experiments provide further evidence that what we see is not a direct reflection of the world but a mental representation of the world that is infused by our emotional experiences.


Attention and Perception

There is another factor that affects sensation and perception: attention. Attention plays a significant role in determining what is sensed versus what is perceived. Imagine you are at a party full of music, chatter, and laughter. You get involved in an interesting conversation with a friend, and you tune out all the background noise. If someone interrupted you to ask what song had just finished playing, you would probably be unable to answer that question.

Watch It

See for yourself how inattentional blindness works by watching this selective attention test from Simons and Chabris (1999):

One of the most interesting demonstrations of how important attention is in determining our perception of the environment occurred in a famous study conducted by Daniel Simons and Christopher Chabris (1999). In this study, participants watched a video of people dressed in black and white passing basketballs. Participants were asked to count the number of times the team in white passed the ball. During the video, a person dressed in a black gorilla costume walks among the two teams. You would think that someone would notice the gorilla, right? Nearly half of the people who watched the video didn’t notice the gorilla at all, despite the fact that he was clearly visible for nine seconds. Because participants were so focused on the number of times the white team was passing the ball, they completely tuned out other visual information. Failure to notice something that is completely visible because of a lack of attention is called inattentional blindness .

In a similar experiment, researchers tested inattentional blindness by asking participants to observe images moving across a computer screen. They were instructed to focus on either white or black objects, disregarding the other color. When a red cross passed across the screen, about one third of subjects did not notice it (Figure 4) (Most, Simons, Scholl, & Chabris, 2000).

Link to Learning

Figure 4. Nearly one third of participants in a study did not notice that a red cross passed on the screen because their attention was focused on the black or white figures. (credit: Cory Zanker)

Culture’s Influence on Perception

Culture plays an important role in molding us into the people we are today. It creates an environment of a shared belief, way of thinking, and method interacting among that group of people. It is dynamic and constantly changing across time. The culture you are born into will shape your eating behavior, such as what you eat, when you eat, and even how you eat. It will influence the clothes you choose to wear and the sports you play. Social norms set forth by your culture will determine how you interact with family members, friends, and strangers. Do you shake their hand when you great someone or kiss them on the cheek? It is clear that your environment shapes much of your outward behavior but did you know that culture also influences brain function, altering the way you think about and perceive the world around you?

The words our culture uses is one such example of this phenomenon. The words our language provides impacts the way we are able to think. In a study done by Frank (2008) Pirahã speakers, a language spoken in small areas of the Amazon, were asked to count varying size groups of objects. However, there are no number words in the Pirahã language. Instead they describe amount do to relative size. Hói discribess a small number hoí describes a slightly larger number, and baágiso describes an even larger number. Thus if the groups were not directly next to each other and relatively the same size, Pirahã speakers could not say which group was larger. Counting is not important in day-to day lives and thus is not represented in their language. The researcher surmised that it was this lack of number language that impacted their perception of quantifies. In this way the words we use limits our cognition and thought. Have you ever been rendered speechless because you did not have the words to express your feelings? Have you ever come across a word in another language that does not exist in your own and are suddenly stunned at how you could have lived for so long without a word to describe that type of experience? In this way, words have a great impact on how we reason and perceive the world.

Furthermore language can also impact the way you think about space. The way one thinks about navigation and spatial knowledge changes depending on whether the language and culture encourages directions based on absolute frames of references (such as north and south) or relative frames of reference ( such as left and right). Kuuk Thaayorre, a small Aboriginal community on the western edge of Cape York in northern Australia, do not have navigational terms such as ‘left,’ ‘right,’ ‘backwards,’ or ‘forwards.’ Instead they describe direction in turns of north, south, east, and west. The Kuuk Thaayorre are much better at staying oriented in unfamiliar places compared to people who speak English. Their language forces them to think about space differently than English speakers, making them constantly aware of where north and south is relative to their current location.

Additionally, what we pay attention to and consequently the information we process is also influenced by culture. Many studies have shown Asian and Western cultures to differ in the judgment of relative and absolute sizing of objects as well as the recollection of focal objects vs background of pictures and videos (Chioa et al., 2010). People raised in Asian cultures recall background context and relative size more accurately. On the other hand, people raised in Western culture are able to more accurately perceive the absolute size of objects and remember the focal objects of images more accurately. Goh and Park (2009) found that the brains of people from Asian and Western cultures activate different areas when performing a figure-ground recognition task.

Culture is all around us, shaping our brain and behavior. Consequently, people from various cultures will process the world differently. Furthermore subcultures exist within cultures. Religions, communities, ad regional accents and customs all work to influence your cognition and perception. As more and more research is executed, the idea of human nature dissipates and we see humanity as a group comprised of unique individuals molded by their complex and intricate culture.

Chiao, J. Y., Harada, T., Komeda, H., Li, Z., Mano, Y., Saito, D., … & Iidaka, T. (2010). Dynamic cultural influences on neural representations of the self. Journal of Cognitive Neuroscience, 22(1), 1-11.

Frank, M. C., Everett, D. L., Fedorenko, E., & Gibson, E. (2008). Number as a cognitive technology: Evidence from Pirahã language and cognition. Cognition, 108(3), 819-824.


5.7 Accuracy and Inaccuracy in Perception

The eyes, ears, nose, tongue, and skin sense the world around us, and in some cases perform preliminary information processing on the incoming data. But by and large, we do not experience sensation—we experience the outcome of perception—the total package that the brain puts together from the pieces it receives through our senses and that the brain creates for us to experience. When we look out the window at a view of the countryside, or when we look at the face of a good friend, we don’t just see a jumble of colors and shapes—we see, instead, an image of a countryside or an image of a friend (Goodale & Milner, 2006).

How the Perceptual System Interprets the Environment

This meaning-making involves the automatic operation of a variety of essential perceptual processes. One of these is sensory interaction—the working together of different senses to create experience. Sensory interaction is involved when taste, smell, and texture combine to create the flavor we experience in food. It is also involved when we enjoy a movie because of the way the images and the music work together.

Although you might think that we understand speech only through our sense of hearing, it turns out that the visual aspect of speech is also important. One example of sensory interaction is shown in the McGurk effectan error in perception that occurs when we misperceive sounds because the audio and visual parts of the speech are mismatched. You can witness the effect yourself by viewing the “Video Clip: The McGurk Effect”.

Video Clip: The McGurk Effect

The McGurk effect is an error in sound perception that occurs when there is a mismatch between the senses of hearing and seeing. You can experience it here.

Other examples of sensory interaction include the experience of nausea that can occur when the sensory information being received from the eyes and the body does not match information from the vestibular system (Flanagan, May, & Dobie, 2004) and synesthesiaan experience in which one sensation (e.g., hearing a sound) creates experiences in another (e.g., vision). Most people do not experience synesthesia, but those who do link their perceptions in unusual ways, for instance, by experiencing color when they taste a particular food or by hearing sounds when they see certain objects (Ramachandran, Hubbard, Robertson, & Sagiv, 2005).

Another important perceptual process is selective attentionthe ability to focus on some sensory inputs while tuning out others. View Note 5.X “Video Clip: Selective Attention” and count the number of times the people playing with the ball pass it to each other. You may find that, like many other people who view it for the first time, you miss something important because you selectively attend to only one aspect of the video (Simons & Chabris, 1999). Perhaps the process of selective attention can help you see why the security guards completely missed the fact that the Chaser group’s motorcade was a fake—they focused on some aspects of the situation, such as the color of the cars and the fact that they were there at all, and completely ignored others (the details of the security information).

Watch this video and carefully count how many times the people pass the ball to each other.

Selective attention also allows us to focus on a single talker at a party while ignoring other conversations that are occurring around us (Broadbent, 1958 Cherry, 1953). Without this automatic selective attention, we’d be unable to focus on the single conversation we want to hear. But selective attention is not complete we also at the same time monitor what’s happening in the channels we are not focusing on. Perhaps you have had the experience of being at a party and talking to someone in one part of the room, when suddenly you hear your name being mentioned by someone in another part of the room. This cocktail-party phenomenon shows us that although selective attention is limiting what we processes, we are nevertheless at the same time doing a lot of unconscious monitoring of the world around us—you didn’t know you were attending to the background sounds of the party, but evidently you were.

A second fundamental process of perception is sensory adaptationa decreased sensitivity to a stimulus after prolonged and constant exposure. When you step into a swimming pool, the water initially feels cold, but after a while you stop noticing it. After prolonged exposure to the same stimulus, our sensitivity toward it diminishes and we no longer perceive it. The ability to adapt to the things that don’t change around us is essential to our survival, as it leaves our sensory receptors free to detect the important and informative changes in our environment and to respond accordingly. We ignore the sounds that our car makes every day, which leaves us free to pay attention to the sounds that are different from normal, and thus likely to need our attention. Our sensory receptors are alert to novelty and are fatigued after constant exposure to the same stimulus.

If sensory adaptation occurs with all senses, why doesn’t an image fade away after we stare at it for a period of time? The answer is that, although we are not aware of it, our eyes are constantly flitting from one angle to the next, making thousands of tiny movements (called saccades) every minute. This constant eye movement guarantees that the image we are viewing always falls on fresh receptor cells. What would happen if we could stop the movement of our eyes? Psychologists have devised a way of testing the sensory adaptation of the eye by attaching an instrument that ensures a constant image is maintained on the eye’s inner surface. Participants are fitted with a contact lens that has miniature slide projector attached to it. Because the projector follows the exact movements of the eye, the same image is always projected, stimulating the same spot, on the retina. Within a few seconds, interesting things begin to happen. The image will begin to vanish, then reappear, only to disappear again, either in pieces or as a whole. Even the eye experiences sensory adaptation (Yarbus, 1967). One of the major problems in perception is to ensure that we always perceive the same object in the same way, despite the fact that the sensations that it creates on our receptors changes dramatically. The ability to perceive a stimulus as constant despite changes in sensation is known as perceptual constancy. Consider our image of a door as it swings. When it is closed, we see it as rectangular, but when it is open, we see only its edge and it appears as a line. But we never perceive the door as changing shape as it swings—perceptual mechanisms take care of the problem for us by allowing us to see a constant shape.

The visual system also corrects for color constancy. Imagine that you are wearing blue jeans and a bright white t-shirt. When you are outdoors, both colors will be at their brightest, but you will still perceive the white t-shirt as bright and the blue jeans as darker. When you go indoors, the light shining on the clothes will be significantly dimmer, but you will still perceive the t-shirt as bright. This is because we put colors in context and see that, compared to its surroundings, the white t-shirt reflects the most light (McCann, 1992). In the same way, a green leaf on a cloudy day may reflect the same wavelength of light as a brown tree branch does on a sunny day. Nevertheless, we still perceive the leaf as green and the branch as brown.

Illusions

Although our perception is very accurate, it is not perfect. Illusions occur when the perceptual processes that normally help us correctly perceive the world around us are fooled by a particular situation so that we see something that does not exist or that is incorrect. In the figure below ( “Optical Illusions as a Result of Brightness Constancy (Left) and Color Constancy (Right)) presents two situations in which our normally accurate perceptions of visual constancy have been fooled.

Another well-known illusion is the Mueller-Lyer illusion (see Figure “The Mueller-Lyre Illusion” below). The line segment in the bottom arrow looks longer to us than the one on the top, even though they are both actually the same length. It is likely that the illusion is, in part, the result of the failure of monocular depth cues—the bottom line looks like an edge that is normally farther away from us, whereas the top one looks like an edge that is normally closer.

The Mueller-Lyre Illusion The Mueller-Lyre illusion makes the line segment at the top of the left picture appear shorter than the one at the bottom. The illusion is caused, in part, by the monocular distance cue of depth—the bottom line looks like an edge that is normally farther away from us, whereas the top one looks like an edge that is normally closer. Edward H. Adelson – Wikimedia Commons – public domain.

The moon illusion refers to the fact that the moon is perceived to be about 50% larger when it is near the horizon than when it is seen overhead, despite the fact that both moons are the same size and cast the same size retinal image. The monocular depth cues of position and aerial perspective create the illusion that things that are lower and more hazy are farther away. The skyline of the horizon (trees, clouds, outlines of buildings) also gives a cue that the moon is far away, compared to a moon at its zenith. If we look at a horizon moon through a tube of rolled up paper, taking away the surrounding horizon cues, the moon will immediately appear smaller.

The Ponzo illusion operates on the same principle. As you can see in the figure below (“The Ponzo Illusion”), the top yellow bar seems longer than the bottom one, but if you measure them you’ll see that they are exactly the same length. The monocular depth cue of linear perspective leads us to believe that, given two similar objects, the distant one can only cast the same size retinal image as the closer object if it is larger. The topmost bar therefore appears longer.

The Ponzo Illusion The Ponzo illusion is caused by a failure of the monocular depth cue of linear perspective: Both bars are the same size even though the top one looks larger. Edward H. Adelson – Wikimedia Commons – public domain.

Illusions demonstrate that our perception of the world around us may be influenced by our prior knowledge. But the fact that some illusions exist in some cases does not mean that the perceptual system is generally inaccurate—in fact, humans normally become so closely in touch with their environment that that the physical body and the particular environment that we sense and perceive becomes embodied—that is, built into and linked with—our cognition, such that the worlds around us become part of our brain (Calvo & Gamila, 2008). The close relationship between people and their environments means that, although illusions can be created in the lab and under some unique situations, they may be less common with active observers in the real world (Runeson, 1988).

The Important Role of Expectations in Perception

Our emotions, mind-set, expectations, and the contexts in which our sensations occur all have a profound influence on perception. People who are warned that they are about to taste something bad rate what they do taste more negatively than people who are told that the taste won’t be so bad (Nitschke et al., 2006), and people perceive a child and adult pair as looking more alike when they are told that they are parent and child (Bressan & Dal Martello, 2002). Similarly, participants who see images of the same baby rate it as stronger and bigger when theyare told it is a boy as opposed to when they are told it is a girl (Stern & Karraker, 1989),and research participants who learn that a child is from a lower-class background perceive the child’s scores on an intelligence test as lower than people who see the same test taken by a child they are told is from an upper-class background (Darley &Gross, 1983). Plassmann, O’Doherty, Shiv, and Rangel (2008)< found that wines were rated more positively and caused greater brain activity in brain areas associated with pleasure when they were said to cost more than when they were said to cost less. And even experts can be fooled: Professional referees tended to assign more penalty cards to soccer teams for videotaped fouls when they were told that the team had a history of aggressive behavior than when they had no such expectation (Jones, Paull, & Erskine, 2002).

Our perceptions are also influenced by our desires and motivations. When we are hungry, food-related words tend to grab our attention more than non-food-related words (Mogg, Bradley, Hyare, & Lee, 1998), we perceive objects that we can reach as bigger than those that we cannot reach (Witt & Proffitt, 2005), and people who favora political candidate’s policies view the candidate’s skin color more positively than do those who oppose the candidate’s policies (Caruso, Mead, & Balcetis, 2009). Even our culture influences perception. Chua, Boland, and Nisbett (2005) showed American and Asian graduate students different images, such as an airplane, an animal ,or a train, against complex backgrounds. They found that (consistent with their overall individualistic orientation)the American students tended to focus more on the foreground image, while Asian students (consistent with their interdependent orientation) paid more attention to the image’s context. Furthermore, Asian-American students focused more or less on the context depending on whether their Asian or their American identity had been activated.

Psychology in Everyday Life: How Understanding Sensation and Perception Can Save Lives

Human factors is the field of psychology that uses psychological knowledge, including the principles of sensation and perception, to improve the development of technology. Human factors has worked on a variety of projects, ranging from nuclear reactor control centers and airplane cockpits to cell phones and websites (Proctor & Van Zandt, 2008). For instance, modern televisions and computer monitors were developed on the basis of the trichromatic color theory, using three color elements placed close enough together so that the colors are blended by the eye. Knowledge of the visual system also helped engineers create new kinds of displays, such as those used on notebook computers and music players, and better understand how using cell phones while driving may contribute to automobile accidents (Lee & Strayer, 2004).

Human factors also has made substantial contributions to airline safety. About two thirds of accidents on commercial airplane flights are caused by human error (Nickerson, 1998). During takeoff, travel, and landing, the pilot simultaneously communicates with ground control, maneuvers the plane, scans the horizon for other aircraft, and operates controls. The need for a useable interface that works easily and naturally with the pilot’s visual perception is essential.

Psychologist Conrad Kraft (1978) hypothesized that as planes land, with no other distance cues visible, pilots may be subjected to a type of moon illusion, in which the city lights beyond the runway appear much larger on the retina than they really are, deceiving the pilot into landing too early. Kraft’s findings caused airlines to institute new flight safety measures, where copilots must call out the altitude progressively during the descent, which has probably decreased the number of landing accidents. These new safety measures included redesigns of older, more crowded and cluttered flight control interfaces that were more or less the same in color. The gauges were also not easy to read. The redesigned digital cockpit showed a marked improvement in usability. More of the controls became color-coded and multi-functional to decrease clutter on the dashboard. Screens now make use of LCD and 3-D graphics. Text sizes are changeable—increasing readability—and many of the functions have become automated, freeing up the pilots concentration for more important activities.

A modern airplane cockpit. This picture was taken inside of an Airbus 320 series commercial airliner and displays the airliner’s advanced “fly-by-wire” piloting system. Note the organization of the controls – similar knobs, dials and buttons are grouped together for optimal usability. Ralf Roletschek – CC-BY-SA 2.5

One important aspect of the redesign was based on the principles of sensory adaptation. Displays that are easy to see in darker conditions quickly become unreadable when the sun shines directly on them. It takes the pilot a relatively long time to adapt to the suddenly much brighter display. Furthermore, perceptual contrast is important. The display cannot be so bright at night that the pilot is unable to see targets in the sky or on the land. Human factors psychologists used these principles to determine the appropriate stimulus intensity needed on these displays so that pilots would be able to read them accurately and quickly under a wide range of conditions. The psychologists accomplished this by developing an automatic control mechanism that senses the ambient light visible through the front cockpit windows and that detects the light falling on the display surface, and then automatically adjusts the intensity of the display for the pilot (Silverstein, Krantz, Gomer, Yeh, & Monty, 1990 Silverstein & Merrifield, 1985).

SUMMARY

  • Sensory interaction occurs when different senses work together, for instance, when taste, smell, and touch together produce the flavor of food.
  • Selective attention allows us to focus on some sensory experiences while tuning out others.
  • Sensory adaptation occurs when we become less sensitive to some aspects of our environment, freeing us to focus on more important changes.
  • Perceptual constancy allows us to perceive an object as the same, despite changes in sensation.
  • Cognitive illusions are examples of how our expectations can influence our perceptions.
  • Our emotions, motivations, desires, and even our culture can influence our perceptions.

Bressan, P., & Dal Martello, M. F. (2002). Talis pater, talis filius: Perceived resemblance and the belief in genetic relatedness. Psychological Science, 13, 213–218.

Broadbent, D. E. (1958). Perception and communication. New York, NY: Pergamon.

Calvo, P., & Gomila, T. (Eds.). (2008). Handbook of cognitive science: An embodied approach. San Diego, CA: Elsevier.

Caruso, E. M., Mead, N. L., & Balcetis, E. (2009). Political partisanship influences perception of biracial candidates’ skin tone. PNAS Proceedings of the National Academy of Sciences of the United States of America, 106(48), 20168–20173.

Cherry, E. C. (1953). Some experiments on the recognition of speech, with one and with two ears. Journal of the Acoustical Society of America, 25, 975–979.

Chua, H. F., Boland, J. E., & Nisbett, R. E. (2005). Cultural variation in eye movements during scene perception. Proceedings of the National Academy of Sciences, 102, 12629–12633.

Darley, J. M., & Gross, P. H. (1983). A hypothesis-confirming bias in labeling effects. Journal of Personality and Social Psychology, 44, 20–33.

Flanagan, M. B., May, J. G., & Dobie, T. G. (2004). The role of vection, eye movements, and postural instability in the etiology of motion sickness. Journal of Vestibular Research: Equilibrium and Orientation, 14(4), 335–346.

Goodale, M., & Milner, D. (2006). One brain—Two visual systems. Psychologist, 19(11), 660–663.

Jones, M. V., Paull, G. C., & Erskine, J. (2002). The impact of a team’s aggressive reputation on the decisions of association football referees. Journal of Sports Sciences, 20, 991–1000.

Kraft, C. (1978). A psychophysical approach to air safety: Simulator studies of visual illusions in night approaches. In H. L. Pick, H. W. Leibowitz, J. E. Singer, A. Steinschneider, & H. W. Steenson (Eds.), Psychology: From research to practice. New York, NY: Plenum Press.

Lee, J., & Strayer, D. (2004). Preface to the special section on driver distraction. Human Factors, 46(4), 583. McCann, J. J. (1992). Rules for color constancy. Ophthalmic and Physiologic Optics, 12(2), 175–177.

Mogg, K., Bradley, B. P., Hyare, H., & Lee, S. (1998). Selective attention to food related stimuli in hunger. Behavior Research & Therapy, 36(2), 227–237.

Nickerson, R. S. (1998). Applied experimental psychology. Applied Psychology: An International Review, 47, 155–173.

Nitschke, J. B., Dixon, G. E., Sarinopoulos, I., Short, S. J., Cohen, J. D., Smith, E. E.,…Davidson, R. J. (2006). Altering expectancy dampens neural response to aversive taste in primary taste cortex. Nature Neuroscience 9, 435–442.

Plassmann, H., O’Doherty, J., Shiv, B., & Rangel, A. (2008). Marketing actions can moderate neural

representations of experienced pleasantness. Proceedings of the National Academy of Sciences, 105(3), 1050–1054.

Proctor, R. W., & Van Zandt, T. (2008). Human factors in simple and complex systems (2nd ed.). Boca Raton, FL: CRC Press.

Ramachandran, V. S., Hubbard, E. M., Robertson, L. C., & Sagiv, N. (2005). The emergence of the human mind: Some clues from synesthesia. In Synesthesia: Perspectives From Cognitive Neuroscience (pp. 147–190). New York, NY: Oxford University Press.

Runeson, S. (1988). The distorted room illusion, equivalent configurations, and the specificity of static optic arrays. Journal of Experimental Psychology: Human Perception and Performance, 14(2), 295–304.

Silverstein, L. D., Krantz, J. H., Gomer, F. E., Yeh, Y., & Monty, R. W. (1990). The effects of spatial sampling and luminance quantization on the image quality of color matrix displays. Journal of the Optical Society of America, Part A, 7, 1955–1968.

Silverstein, L. D., & Merrifield, R. M. (1985). The development and evaluation of color systems for airborne applications: Phase I Fundamental visual, perceptual, and display systems considerations (Tech. Report DOT/FAA/PM085019). Washington, DC: Federal Aviation Administration.

Simons, D. J., & Chabris, C. F. (1999). Gorillas in our midst: Sustained inattentional blindness for dynamic events. Perception, 28(9), 1059–1074.

Stern, M., & Karraker, K. H. (1989). Sex stereotyping of infants: A review of gender labeling studies. Sex Roles, 20(9–10), 501–522.

Witt, J. K., & Proffitt, D. R. (2005). See the ball, hit the ball: Apparent ball size is correlated with batting average. Psychological Science, 16(12), 937–938.

Yarbus, A. L. (1967). Eye movements and vision. New York, NY: Plenum Press

Exercises

Review Questions:

1. In what way does the visual system correct for the effect of sensory adaptation?

a. The visual system does not correct for the effect of sensory adaptation.

b. The visual system uses rapid blinking eye movements to inhibit sensory adaptation.

c. The visual system turns off rods and cones to prevent sensory adaptation.

d. The visual system utilizes a series of rapidly shifting eye movements to “refresh”

2. Which of the following circumstances best describes someone who is experiencing the phenomenon of synesthesia in the given environment:

There is a room in which a baby is crying from spontaneous blasts from an airhorn pressed by the venerable ghost of John Watson.

a. Albert (not the baby) is also in the room but can only hear the baby crying and not the airhorn.

b. Mary is unable to tell apart the blasts from the airhorn or the cries of the baby, and instead hears a fog-horn like noise.

c. John, upon hearing the baby cry, starts to see the color red in the extremities of his visual field.

d. William, seeing the illuminated, ghostly visage of John Watson, also sees the color red in the extremities of his visual field.

3. True or False: The presence of optical illusions demonstrate that our perceptions are influenced by previous experiences to the presented visual stimuli and the accuracy of our memory when recalling such experiences with the stimuli.

Answers to Exercises

Review Questions:

Cocktail-party Phenomenon: a phenomenon displaying one’s ability to unconsciously monitor select stimuli in one’s background, such as in a cocktail-party in which you hear your name being called from across the room even if you are selectively fixating your attention on the person directly in front of you.

Human factors: the field of psychology that uses psychological knowledge, including the principles of sensation and perception, to improve the development of technology.

Illusions: occur when the perceptual processes that normally help us correctly perceive the world around us are fooled by a particular situation so that we see something that does not exist or that is incorrect

McGurk effect: error in sound perception that occurs when there is a mismatch between the senses of hearing and seeing.

Perceptual constancy: the ability to perceive a stimulus as constant despite changes in sensation

Selective attention: the ability to focus on some sensory inputs while tuning out others

Sensory adaptation: decreased sensitivity to a stimulus after prolonged and constant exposure

Sensory interaction: the working together of different senses to create experience.

Synesthesia: an experience in which one sensation (e.g., hearing a sound) creates experiences in another (e.g., vision).


Culture’s Influence on Perception

Culture plays an important role in molding us into the people we are today. It creates an environment of a shared belief, way of thinking, and method interacting among that group of people. It is dynamic and constantly changing across time. The culture you are born into will shape your eating behavior, such as what you eat, when you eat, and even how you eat. It will influence the clothes you choose to wear and the sports you play. Social norms set forth by your culture will determine how you interact with family members, friends, and strangers. Do you shake their hand when you great someone or kiss them on the cheek? It is clear that your environment shapes much of your outward behavior but did you know that culture also influences brain function, altering the way you think about and perceive the world around you?

The words our culture uses is one such example of this phenomenon. The words our language provides impacts the way we are able to think. In a study done by Frank (2008) Pirahã speakers, a language spoken in small areas of the Amazon, were asked to count varying size groups of objects. However, there are no number words in the Pirahã language. Instead they describe amount do to relative size. Hói discribess a small number hoí describes a slightly larger number, and baágiso describes an even larger number. Thus if the groups were not directly next to each other and relatively the same size, Pirahã speakers could not say which group was larger. Counting is not important in day-to day lives and thus is not represented in their language. The researcher surmised that it was this lack of number language that impacted their perception of quantifies. In this way the words we use limits our cognition and thought. Have you ever been rendered speechless because you did not have the words to express your feelings? Have you ever come across a word in another language that does not exist in your own and are suddenly stunned at how you could have lived for so long without a word to describe that type of experience? In this way, words have a great impact on how we reason and perceive the world.

Furthermore language can also impact the way you think about space. The way one thinks about navigation and spatial knowledge changes depending on whether the language and culture encourages directions based on absolute frames of references (such as north and south) or relative frames of reference ( such as left and right). Kuuk Thaayorre, a small Aboriginal community on the western edge of Cape York in northern Australia, do not have navigational terms such as ‘left,’ ‘right,’ ‘backwards,’ or ‘forwards.’ Instead they describe direction in turns of north, south, east, and west. The Kuuk Thaayorre are much better at staying oriented in unfamiliar places compared to people who speak English. Their language forces them to think about space differently than English speakers, making them constantly aware of where north and south is relative to their current location.

Additionally, what we pay attention to and consequently the information we process is also influenced by culture. Many studies have shown Asian and Western cultures to differ in the judgment of relative and absolute sizing of objects as well as the recollection of focal objects vs background of pictures and videos (Chioa et al., 2010). People raised in Asian cultures recall background context and relative size more accurately. On the other hand, people raised in Western culture are able to more accurately perceive the absolute size of objects and remember the focal objects of images more accurately. Goh and Park (2009) found that the brains of people from Asian and Western cultures activate different areas when performing a figure-ground recognition task.

Culture is all around us, shaping our brain and behavior. Consequently, people from various cultures will process the world differently. Furthermore subcultures exist within cultures. Religions, communities, ad regional accents and customs all work to influence your cognition and perception. As more and more research is executed, the idea of human nature dissipates and we see humanity as a group comprised of unique individuals molded by their complex and intricate culture.

Chiao, J. Y., Harada, T., Komeda, H., Li, Z., Mano, Y., Saito, D., … & Iidaka, T. (2010). Dynamic cultural influences on neural representations of the self. Journal of Cognitive Neuroscience, 22(1), 1-11.

Frank, M. C., Everett, D. L., Fedorenko, E., & Gibson, E. (2008). Number as a cognitive technology: Evidence from Pirahã language and cognition. Cognition, 108(3), 819-824.


The emotions we feel may shape what we see

Our emotional state in a given moment may influence what we see, according to findings published in Psychological Science, a journal of the Association for Psychological Science. In two experiments, researchers found that participants saw a neutral face as smiling more when it was paired with an unseen positive image.

The research shows that humans are active perceivers, say psychological scientist Erika Siegel of the University of California, San Francisco and her coauthors.

"We do not passively detect information in the world and then react to it -- we construct perceptions of the world as the architects of our own experience. Our affective feelings are a critical determinant of the experience we create," the researchers explain. "That is, we do not come to know the world through only our external senses -- we see the world differently when we feel pleasant or unpleasant."

In previous studies, Siegel and colleagues found that influencing people's emotional states outside of conscious awareness shifted their first impressions of neutral faces, making faces seem more or less likeable, trustworthy, and reliable. In this research, they wanted to see if changing people's emotional states outside awareness might actually change how they see the neutral faces.

Using a technique called continuous flash suppression, the researchers were able to present stimuli to participants without them knowing it. In one experiment, 43 participants had a series of flashing images, which alternated between a pixelated image and a neutral face, presented to their dominant eye. At the same time, a low-contrast image of a smiling, scowling, or neutral face was presented to their nondominant eye -- typically, this image will be suppressed by the stimulus presented to the dominant eye and participants will not consciously experience it.

At the end of each trial, a set of five faces appeared and participants picked the one that best matched the face they saw during the trial.

The face that was presented to participants' dominant eye was always neutral. But they tended to select faces that were smiling more as the best match if the image that was presented outside of their awareness showed a person who was smiling as opposed to neutral or scowling

In a second experiment, the researchers included an objective measure of awareness, asking participants to guess the orientation of the suppressed face. Those who correctly guessed the orientation at better than chance levels were not included in subsequent analyses. Again, the results indicated that unseen positive faces changed participants' perception of the visible neutral face.

Given that studies often show negative stimuli as having greater influence on behavior and decision making, the robust effect of positive faces in this research is intriguing and an interesting area for future exploration, the researchers note.

Siegel and colleagues add that their findings could have broad, real-world implications that extend from everyday social interactions to situations with more severe consequences, such as when judges or jury members have to evaluate whether a defendant is remorseful.

Ultimately, these experiments provide further evidence that what we see is not a direct reflection of the world but a mental representation of the world that is infused by our emotional experiences.


Self-Concept, Self-Image and Self-Esteem

In this study note we explain the three related ideas of self-concept, self-image and self-esteem and how emotional development changes through the life stages.

Self-Concept

Self-concept is how someone sees themselves and the perception that they hold about their abilities. There are various factors that can affect self-concept, these include: age, sexual orientation, gender and religion. The self-concept is also made up of a combination of self-esteem and self-image.

Self-esteem refers to a person’s feelings of self-worth or the value that they place on themselves.

There are a number of characteristics of high and low self-esteem.

Characteristics of high self-esteem

  • Willing to try new things in their life
  • Can cope well under pressure
  • Emotionally stable and confident
  • Happy to share their ideas and experiences

Characteristics of low self-esteem

  • Feels worthless
  • Reluctant to try new things
  • Struggles in new or challenging circumstances
  • Do not value their own opinions and sensitive to the opinions of others

Factors affecting self esteem

  • Parents/carers teaching problem solving skills from a young age (so that a child feels a sense of achievement) can lead to a positive self-esteem.
  • Learning difficulties at school can lead to a child struggling to complete work or maintain friendships, which can lead to negative self-esteem.

Self-image refers to the way an individual sees themselves, both physically and mentally. An individual’s self-image is developed over time and influenced by the experiences they have encountered.

There are a number of characteristics of a positive and negative self-image.

Characteristics of a positive self-image

  • Feels confident
  • Compares themselves positively with peers
  • Content with how they look and has belief in their own ability
  • Positive feedback received from friends and family on looks and abilities

Characteristics of a negative self-image

  • Doubts own ability
  • Compares themselves negatively with peers and images on social media/TV/magazines
  • Received negative comments from friends and family on physical appearance or mental ability

Factors affecting self-image

  • Early childhood experiences and social interactions eg parents who pass positive comments to a child can help contribute to a positive self-image.
  • Life events or roles eg a child who is captain of the rugby team is more likely to have a positive self-image that a child who is bullied at school

Emotional Development through the life stages

During this stage, infants develop a sense of self and positive self-esteem through secure attachments with their caregivers. This starts with their basic needs being met as a baby.

Early Childhood

By the age of four, the child’s self-esteem develops further through the support they receive outside of the family. Being able to solve problems through puzzles will enhance self-esteem, as will involving the children in scenarios where their opinion is sought. Children who do not receive these experiences may develop low self-esteem.

Adolescence

Several factors affect self-esteem during adolescence. These can include stress within the home, or at school, or a combination of the two. Coupled with the changes that occur during puberty, these can all have an impact on self-image too.

Being bullied or not being accepted by your peers can have detrimental effects on a young person’s self-esteem and can feed into way they feel about themselves. This can lead to anxiety and depression and a sense of not belonging, all characteristics of having low self-worth. This can be intensified by peer pressure, the use of images in the media, social media and the increase in cyberbullying.

Self-esteem continues to develop through adulthood and an individual’s self-esteem may increase through the achievements they have made which, in turn, increases self-worth. During adulthood a person develops a real understanding of who they are and how to deal with situations more effectively and with more confidence.


Influences on Top-Down Processing

According to Gregory (1970) different factors can influence top-down processing such as expectations, emotion, motivation and culture. This is known as perceptual set theory.

The context or situation in which we have previously perceived information can influence future expectations when receiving new information under similar circumstances.

To no surprise, previous experiences undoubtedly influence how new information is perceived as we, as humans, use the knowledge that we gained from prior events in order to construct expectations for perceiving new information.

Our brains are shaped by the external world and through context and experience our perception is also shaped by the external world.

For this reason, the influence of culture on shaping our perceptions cannot be ignored as culture creates differences in contexts and experiences that individuals draw from when perceiving new information (Deregowski, 1972).

Motivation can also influence top-down processing as you may be more motivated to perceive things depending on your needs and desires (Swets, 1964).

For example, let’s say you are waiting for a phone call that determines whether or not you were chosen for a recent position that you have interviewed for, and you hear the phone ring when you are taking a shower, when in fact, the phone never rang.

This is a perfect example of how motivation can influence perception because your need and desire for the phone to ring with that very important call is so strong that you are imagining hearing the phone ring when it is not in fact ringing at all.


Attention and Perception

There is another factor that affects sensation and perception: attention. Attention plays a significant role in determining what is sensed versus what is perceived. Imagine you are at a party full of music, chatter, and laughter. You get involved in an interesting conversation with a friend, and you tune out all the background noise. If someone interrupted you to ask what song had just finished playing, you would probably be unable to answer that question.

Watch It

See for yourself how inattentional blindness works by watching this selective attention test from Simons and Chabris (1999):

One of the most interesting demonstrations of how important attention is in determining our perception of the environment occurred in a famous study conducted by Daniel Simons and Christopher Chabris (1999). In this study, participants watched a video of people dressed in black and white passing basketballs. Participants were asked to count the number of times the team in white passed the ball. During the video, a person dressed in a black gorilla costume walks among the two teams. You would think that someone would notice the gorilla, right? Nearly half of the people who watched the video didn’t notice the gorilla at all, despite the fact that he was clearly visible for nine seconds. Because participants were so focused on the number of times the white team was passing the ball, they completely tuned out other visual information. Failure to notice something that is completely visible because of a lack of attention is called inattentional blindness .

In a similar experiment, researchers tested inattentional blindness by asking participants to observe images moving across a computer screen. They were instructed to focus on either white or black objects, disregarding the other color. When a red cross passed across the screen, about one third of subjects did not notice it (Figure 4) (Most, Simons, Scholl, & Chabris, 2000).

Link to Learning

Figure 4. Nearly one third of participants in a study did not notice that a red cross passed on the screen because their attention was focused on the black or white figures. (credit: Cory Zanker)

5.7 Accuracy and Inaccuracy in Perception

The eyes, ears, nose, tongue, and skin sense the world around us, and in some cases perform preliminary information processing on the incoming data. But by and large, we do not experience sensation—we experience the outcome of perception—the total package that the brain puts together from the pieces it receives through our senses and that the brain creates for us to experience. When we look out the window at a view of the countryside, or when we look at the face of a good friend, we don’t just see a jumble of colors and shapes—we see, instead, an image of a countryside or an image of a friend (Goodale & Milner, 2006).

How the Perceptual System Interprets the Environment

This meaning-making involves the automatic operation of a variety of essential perceptual processes. One of these is sensory interaction—the working together of different senses to create experience. Sensory interaction is involved when taste, smell, and texture combine to create the flavor we experience in food. It is also involved when we enjoy a movie because of the way the images and the music work together.

Although you might think that we understand speech only through our sense of hearing, it turns out that the visual aspect of speech is also important. One example of sensory interaction is shown in the McGurk effectan error in perception that occurs when we misperceive sounds because the audio and visual parts of the speech are mismatched. You can witness the effect yourself by viewing the “Video Clip: The McGurk Effect”.

Video Clip: The McGurk Effect

The McGurk effect is an error in sound perception that occurs when there is a mismatch between the senses of hearing and seeing. You can experience it here.

Other examples of sensory interaction include the experience of nausea that can occur when the sensory information being received from the eyes and the body does not match information from the vestibular system (Flanagan, May, & Dobie, 2004) and synesthesiaan experience in which one sensation (e.g., hearing a sound) creates experiences in another (e.g., vision). Most people do not experience synesthesia, but those who do link their perceptions in unusual ways, for instance, by experiencing color when they taste a particular food or by hearing sounds when they see certain objects (Ramachandran, Hubbard, Robertson, & Sagiv, 2005).

Another important perceptual process is selective attentionthe ability to focus on some sensory inputs while tuning out others. View Note 5.X “Video Clip: Selective Attention” and count the number of times the people playing with the ball pass it to each other. You may find that, like many other people who view it for the first time, you miss something important because you selectively attend to only one aspect of the video (Simons & Chabris, 1999). Perhaps the process of selective attention can help you see why the security guards completely missed the fact that the Chaser group’s motorcade was a fake—they focused on some aspects of the situation, such as the color of the cars and the fact that they were there at all, and completely ignored others (the details of the security information).

Watch this video and carefully count how many times the people pass the ball to each other.

Selective attention also allows us to focus on a single talker at a party while ignoring other conversations that are occurring around us (Broadbent, 1958 Cherry, 1953). Without this automatic selective attention, we’d be unable to focus on the single conversation we want to hear. But selective attention is not complete we also at the same time monitor what’s happening in the channels we are not focusing on. Perhaps you have had the experience of being at a party and talking to someone in one part of the room, when suddenly you hear your name being mentioned by someone in another part of the room. This cocktail-party phenomenon shows us that although selective attention is limiting what we processes, we are nevertheless at the same time doing a lot of unconscious monitoring of the world around us—you didn’t know you were attending to the background sounds of the party, but evidently you were.

A second fundamental process of perception is sensory adaptationa decreased sensitivity to a stimulus after prolonged and constant exposure. When you step into a swimming pool, the water initially feels cold, but after a while you stop noticing it. After prolonged exposure to the same stimulus, our sensitivity toward it diminishes and we no longer perceive it. The ability to adapt to the things that don’t change around us is essential to our survival, as it leaves our sensory receptors free to detect the important and informative changes in our environment and to respond accordingly. We ignore the sounds that our car makes every day, which leaves us free to pay attention to the sounds that are different from normal, and thus likely to need our attention. Our sensory receptors are alert to novelty and are fatigued after constant exposure to the same stimulus.

If sensory adaptation occurs with all senses, why doesn’t an image fade away after we stare at it for a period of time? The answer is that, although we are not aware of it, our eyes are constantly flitting from one angle to the next, making thousands of tiny movements (called saccades) every minute. This constant eye movement guarantees that the image we are viewing always falls on fresh receptor cells. What would happen if we could stop the movement of our eyes? Psychologists have devised a way of testing the sensory adaptation of the eye by attaching an instrument that ensures a constant image is maintained on the eye’s inner surface. Participants are fitted with a contact lens that has miniature slide projector attached to it. Because the projector follows the exact movements of the eye, the same image is always projected, stimulating the same spot, on the retina. Within a few seconds, interesting things begin to happen. The image will begin to vanish, then reappear, only to disappear again, either in pieces or as a whole. Even the eye experiences sensory adaptation (Yarbus, 1967). One of the major problems in perception is to ensure that we always perceive the same object in the same way, despite the fact that the sensations that it creates on our receptors changes dramatically. The ability to perceive a stimulus as constant despite changes in sensation is known as perceptual constancy. Consider our image of a door as it swings. When it is closed, we see it as rectangular, but when it is open, we see only its edge and it appears as a line. But we never perceive the door as changing shape as it swings—perceptual mechanisms take care of the problem for us by allowing us to see a constant shape.

The visual system also corrects for color constancy. Imagine that you are wearing blue jeans and a bright white t-shirt. When you are outdoors, both colors will be at their brightest, but you will still perceive the white t-shirt as bright and the blue jeans as darker. When you go indoors, the light shining on the clothes will be significantly dimmer, but you will still perceive the t-shirt as bright. This is because we put colors in context and see that, compared to its surroundings, the white t-shirt reflects the most light (McCann, 1992). In the same way, a green leaf on a cloudy day may reflect the same wavelength of light as a brown tree branch does on a sunny day. Nevertheless, we still perceive the leaf as green and the branch as brown.

Illusions

Although our perception is very accurate, it is not perfect. Illusions occur when the perceptual processes that normally help us correctly perceive the world around us are fooled by a particular situation so that we see something that does not exist or that is incorrect. In the figure below ( “Optical Illusions as a Result of Brightness Constancy (Left) and Color Constancy (Right)) presents two situations in which our normally accurate perceptions of visual constancy have been fooled.

Another well-known illusion is the Mueller-Lyer illusion (see Figure “The Mueller-Lyre Illusion” below). The line segment in the bottom arrow looks longer to us than the one on the top, even though they are both actually the same length. It is likely that the illusion is, in part, the result of the failure of monocular depth cues—the bottom line looks like an edge that is normally farther away from us, whereas the top one looks like an edge that is normally closer.

The Mueller-Lyre Illusion The Mueller-Lyre illusion makes the line segment at the top of the left picture appear shorter than the one at the bottom. The illusion is caused, in part, by the monocular distance cue of depth—the bottom line looks like an edge that is normally farther away from us, whereas the top one looks like an edge that is normally closer. Edward H. Adelson – Wikimedia Commons – public domain.

The moon illusion refers to the fact that the moon is perceived to be about 50% larger when it is near the horizon than when it is seen overhead, despite the fact that both moons are the same size and cast the same size retinal image. The monocular depth cues of position and aerial perspective create the illusion that things that are lower and more hazy are farther away. The skyline of the horizon (trees, clouds, outlines of buildings) also gives a cue that the moon is far away, compared to a moon at its zenith. If we look at a horizon moon through a tube of rolled up paper, taking away the surrounding horizon cues, the moon will immediately appear smaller.

The Ponzo illusion operates on the same principle. As you can see in the figure below (“The Ponzo Illusion”), the top yellow bar seems longer than the bottom one, but if you measure them you’ll see that they are exactly the same length. The monocular depth cue of linear perspective leads us to believe that, given two similar objects, the distant one can only cast the same size retinal image as the closer object if it is larger. The topmost bar therefore appears longer.

The Ponzo Illusion The Ponzo illusion is caused by a failure of the monocular depth cue of linear perspective: Both bars are the same size even though the top one looks larger. Edward H. Adelson – Wikimedia Commons – public domain.

Illusions demonstrate that our perception of the world around us may be influenced by our prior knowledge. But the fact that some illusions exist in some cases does not mean that the perceptual system is generally inaccurate—in fact, humans normally become so closely in touch with their environment that that the physical body and the particular environment that we sense and perceive becomes embodied—that is, built into and linked with—our cognition, such that the worlds around us become part of our brain (Calvo & Gamila, 2008). The close relationship between people and their environments means that, although illusions can be created in the lab and under some unique situations, they may be less common with active observers in the real world (Runeson, 1988).

The Important Role of Expectations in Perception

Our emotions, mind-set, expectations, and the contexts in which our sensations occur all have a profound influence on perception. People who are warned that they are about to taste something bad rate what they do taste more negatively than people who are told that the taste won’t be so bad (Nitschke et al., 2006), and people perceive a child and adult pair as looking more alike when they are told that they are parent and child (Bressan & Dal Martello, 2002). Similarly, participants who see images of the same baby rate it as stronger and bigger when theyare told it is a boy as opposed to when they are told it is a girl (Stern & Karraker, 1989),and research participants who learn that a child is from a lower-class background perceive the child’s scores on an intelligence test as lower than people who see the same test taken by a child they are told is from an upper-class background (Darley &Gross, 1983). Plassmann, O’Doherty, Shiv, and Rangel (2008)< found that wines were rated more positively and caused greater brain activity in brain areas associated with pleasure when they were said to cost more than when they were said to cost less. And even experts can be fooled: Professional referees tended to assign more penalty cards to soccer teams for videotaped fouls when they were told that the team had a history of aggressive behavior than when they had no such expectation (Jones, Paull, & Erskine, 2002).

Our perceptions are also influenced by our desires and motivations. When we are hungry, food-related words tend to grab our attention more than non-food-related words (Mogg, Bradley, Hyare, & Lee, 1998), we perceive objects that we can reach as bigger than those that we cannot reach (Witt & Proffitt, 2005), and people who favora political candidate’s policies view the candidate’s skin color more positively than do those who oppose the candidate’s policies (Caruso, Mead, & Balcetis, 2009). Even our culture influences perception. Chua, Boland, and Nisbett (2005) showed American and Asian graduate students different images, such as an airplane, an animal ,or a train, against complex backgrounds. They found that (consistent with their overall individualistic orientation)the American students tended to focus more on the foreground image, while Asian students (consistent with their interdependent orientation) paid more attention to the image’s context. Furthermore, Asian-American students focused more or less on the context depending on whether their Asian or their American identity had been activated.

Psychology in Everyday Life: How Understanding Sensation and Perception Can Save Lives

Human factors is the field of psychology that uses psychological knowledge, including the principles of sensation and perception, to improve the development of technology. Human factors has worked on a variety of projects, ranging from nuclear reactor control centers and airplane cockpits to cell phones and websites (Proctor & Van Zandt, 2008). For instance, modern televisions and computer monitors were developed on the basis of the trichromatic color theory, using three color elements placed close enough together so that the colors are blended by the eye. Knowledge of the visual system also helped engineers create new kinds of displays, such as those used on notebook computers and music players, and better understand how using cell phones while driving may contribute to automobile accidents (Lee & Strayer, 2004).

Human factors also has made substantial contributions to airline safety. About two thirds of accidents on commercial airplane flights are caused by human error (Nickerson, 1998). During takeoff, travel, and landing, the pilot simultaneously communicates with ground control, maneuvers the plane, scans the horizon for other aircraft, and operates controls. The need for a useable interface that works easily and naturally with the pilot’s visual perception is essential.

Psychologist Conrad Kraft (1978) hypothesized that as planes land, with no other distance cues visible, pilots may be subjected to a type of moon illusion, in which the city lights beyond the runway appear much larger on the retina than they really are, deceiving the pilot into landing too early. Kraft’s findings caused airlines to institute new flight safety measures, where copilots must call out the altitude progressively during the descent, which has probably decreased the number of landing accidents. These new safety measures included redesigns of older, more crowded and cluttered flight control interfaces that were more or less the same in color. The gauges were also not easy to read. The redesigned digital cockpit showed a marked improvement in usability. More of the controls became color-coded and multi-functional to decrease clutter on the dashboard. Screens now make use of LCD and 3-D graphics. Text sizes are changeable—increasing readability—and many of the functions have become automated, freeing up the pilots concentration for more important activities.

A modern airplane cockpit. This picture was taken inside of an Airbus 320 series commercial airliner and displays the airliner’s advanced “fly-by-wire” piloting system. Note the organization of the controls – similar knobs, dials and buttons are grouped together for optimal usability. Ralf Roletschek – CC-BY-SA 2.5

One important aspect of the redesign was based on the principles of sensory adaptation. Displays that are easy to see in darker conditions quickly become unreadable when the sun shines directly on them. It takes the pilot a relatively long time to adapt to the suddenly much brighter display. Furthermore, perceptual contrast is important. The display cannot be so bright at night that the pilot is unable to see targets in the sky or on the land. Human factors psychologists used these principles to determine the appropriate stimulus intensity needed on these displays so that pilots would be able to read them accurately and quickly under a wide range of conditions. The psychologists accomplished this by developing an automatic control mechanism that senses the ambient light visible through the front cockpit windows and that detects the light falling on the display surface, and then automatically adjusts the intensity of the display for the pilot (Silverstein, Krantz, Gomer, Yeh, & Monty, 1990 Silverstein & Merrifield, 1985).

SUMMARY

  • Sensory interaction occurs when different senses work together, for instance, when taste, smell, and touch together produce the flavor of food.
  • Selective attention allows us to focus on some sensory experiences while tuning out others.
  • Sensory adaptation occurs when we become less sensitive to some aspects of our environment, freeing us to focus on more important changes.
  • Perceptual constancy allows us to perceive an object as the same, despite changes in sensation.
  • Cognitive illusions are examples of how our expectations can influence our perceptions.
  • Our emotions, motivations, desires, and even our culture can influence our perceptions.

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Exercises

Review Questions:

1. In what way does the visual system correct for the effect of sensory adaptation?

a. The visual system does not correct for the effect of sensory adaptation.

b. The visual system uses rapid blinking eye movements to inhibit sensory adaptation.

c. The visual system turns off rods and cones to prevent sensory adaptation.

d. The visual system utilizes a series of rapidly shifting eye movements to “refresh”

2. Which of the following circumstances best describes someone who is experiencing the phenomenon of synesthesia in the given environment:

There is a room in which a baby is crying from spontaneous blasts from an airhorn pressed by the venerable ghost of John Watson.

a. Albert (not the baby) is also in the room but can only hear the baby crying and not the airhorn.

b. Mary is unable to tell apart the blasts from the airhorn or the cries of the baby, and instead hears a fog-horn like noise.

c. John, upon hearing the baby cry, starts to see the color red in the extremities of his visual field.

d. William, seeing the illuminated, ghostly visage of John Watson, also sees the color red in the extremities of his visual field.

3. True or False: The presence of optical illusions demonstrate that our perceptions are influenced by previous experiences to the presented visual stimuli and the accuracy of our memory when recalling such experiences with the stimuli.

Answers to Exercises

Review Questions:

Cocktail-party Phenomenon: a phenomenon displaying one’s ability to unconsciously monitor select stimuli in one’s background, such as in a cocktail-party in which you hear your name being called from across the room even if you are selectively fixating your attention on the person directly in front of you.

Human factors: the field of psychology that uses psychological knowledge, including the principles of sensation and perception, to improve the development of technology.

Illusions: occur when the perceptual processes that normally help us correctly perceive the world around us are fooled by a particular situation so that we see something that does not exist or that is incorrect

McGurk effect: error in sound perception that occurs when there is a mismatch between the senses of hearing and seeing.

Perceptual constancy: the ability to perceive a stimulus as constant despite changes in sensation

Selective attention: the ability to focus on some sensory inputs while tuning out others

Sensory adaptation: decreased sensitivity to a stimulus after prolonged and constant exposure

Sensory interaction: the working together of different senses to create experience.

Synesthesia: an experience in which one sensation (e.g., hearing a sound) creates experiences in another (e.g., vision).


Mass Communication Talk

Q.5:Define perception and identify some psychological factors that influence perception. Also highlight the role of perception in mass communication.

Perception, Psychological Factors that Influence Perception in Mass Communication

Much of the research showing that perception is influenced by assumptions has come from a group of researchers working at one time or another at Princeton University. These researchers, who have included Adelbert Ames, Jr., Hadley Cantril, Edward Engels, Albert Hastorf, William H. Ittelson, Franklin p. Kilpatrick, and Hans Tech, have presented what has been called the transactional view of perception. The concept is abstract and somewhat philosophical, but essentially it means that both the perceiver and the world are active participants in an act of perception (Tech & MacLean, 1962).

The transactional thinkers have developed a number of convincing demon­strations that perception is based on assumptions. One of the most striking, invented by Adelbert Ames, Jr., is called the monocular distorted room. This room is constructed so that the rear wall is a trapezoid, with the vertical distance up and down the left edge of the wall longer than the vertical distance up and down the right edge of the wall. The rear wall is positioned at an angle so that the left edge is farther back than the right edge. This angle is carefully selected so that the room will appear to be an ordinary rectangular room to an observer looking through a small hole at the front of the room. If two people walk into the room and stand in the rear corners, something interesting happens. The one on the right appears to a viewer looking through the hole to be very large because he or she is closer to the viewer and fills most of the distance from the floor to the ceiling. The one on the left appears to be very small because he or she is farther away and fills less of the distance from the floor to the ceiling. This illusion occurs because the mind of the viewer is assuming that the rear wall is parallel to the front wall of the room. This assumption is based on prior experience with other rooms that looked similar. The illusion is so strong that if the two people in the corners switch places, one will appear to grow larger and the other will appear to get smaller, right before the viewer’s eye.

Psychological Factors that Influence Perception:

Cultural Expectations and Perception

Some of the most striking evidence for the influence of cultural expectations on perception comes from research on binocular rivalry (Bagby, 1957). It is possible to construct a device that has two eyepieces like a pair of binoculars, but can be used to present a different picture to each eye. When this is done, people seldom see both pictures. They more often see one picture and not the other or one picture and then the other. Sometimes they see a mixture of some elements of each picture, but this usually occurs after seeing one picture alone first. Bagby used this instrument to investigate the effect of cultural background on perception.

Subjects were 12 Americans (6 males and 6 females) and 12 Mexicans (6 males and 6 females). Except for one matched pair made up of a person from each country, the subjects had not traveled outside their own country. Bagby prepared ten pairs of photographic slides, each pair containing a picture from the American culture and a picture from the Mexican culture. One pair, for instance, showed a baseball scene and a bullfight scene. Subjects were exposed to each slide for 60 seconds and asked to describe what they saw. The assignment of the Mexican or the American picture to the left or right eye was randomized to eliminatethe effect of eye dominance. The first 15 seconds of viewing for each slide were scored for which scene was dominant—the Mexican or

TABLE :Perceptual predominance in 10 pairs of pictures for Mexican and American subjects

Trials Where

source From J. W. Baby, “A Cross-cultural Study of Perceptual Predominance in Binocular Rivalry,” Journal of Abnormal and Social Psychology 54 (1957): 333. Copyright © 1957 by the American Psychological Association, Reprinted by permission, the American. Dominance was determined by the scene that was reported first or was reported as showing up for the longest period of time. The results (Table 4.1) indicate a strong tendency for subjects to see the scenes from their own culture rather than the scenes from an unfamiliar culture.

Motivation and Perception:

One of a number of experiments that shows the effect of motivation on percep­tion was done by McClelland and Atkinson (1948). The type of motivation being investigated was hunger. Subjects were Navy men waiting for admission to a submarine training school. One group had gone 16 hours without food, a second 4 hours without food, and the third 1 hour without food. All subjects were told they were participating in a test of their ability to respond to visual stimulation at very low levels. The men went through 12 trials in which a picture was supposedly projected, but actually nothing was projected at all. To make this realistic, during the instructions they were shown a picture of a car and then the illumination was turned down until the car was only faintly visible. In some of the trials subjects were given clues such as: “Three objects on a table. What are they?”

The results (Table 4.2) showed that the frequency of food-related responses increased reliably as the hours of food deprivation increased. Furthermore, in another phase of the experiment food-related objects were judged larger than neutral objects by hungry subjects but not by subjects who had recently eaten.

Mood and Perception:

An experiment using hypnosis demonstrated that mood has an effect on percep­tion. Leuba and Lucas (1945) hypnotized subjects, suggested to them that they were experiencing a certain mood, and then asked them to tell what they saw

in a picture. Each subject was put in a happy mood and then shown six pictures. Then the subject was told to forget the pictures and what had been said about them and was put in a critical mood and again shown the same six pictures. Finally, the subject was given the same treatment once more except that the suggested mood was anxious. The descriptions of the pictures were drastically different depending on the mood the person was in. They differed not only in the train of thought the pictures suggested but also in the details noticed.

One picture showed some young people digging in a swampy area. Here is one subject’s description of that picture while in a happy mood:

It looks like fun reminds me of summer. That’s what life is for working out in the open, really living—digging in the dirt, planting, watching things grow.

Here is the same subject describing the same picture while in a critical mood:

Pretty horrible land. There ought to be something more useful for kids of that age to do instead of digging in that stuff. It’s filthy and dirty and good for nothing.

Here is the same subject describing the same picture while in an anxious mood:

They’re going to get hurt or cut. There should be someone older there who knows what to do in case of an accident. I wonder how deep the water is.

Attitude and Perception:

The effects of attitude on perception were documented in a study of perception of a football game by Hastorf and Cantrii (1954). The 1951 football clash between Dartmouth and Princeton was an exciting and controversial one. Princeton’s star player Dick Kazmaier was taken out of the game in the second quarter with a broken nose. In the third quarter, a Dartmouth player received a broken leg. Discussion of the game continued for weeks, with editorials in the two campus newspapers charging the other school with rough play. Hastorf and Cantrii took advantage of this situation to conduct a study in perception. They showed a film of the game to two groups: two fraternities at Dartmouth and two undergraduate clubs at Princeton. Students from both schools saw about the same number of infractions by the Princeton team. But Princeton students saw an average of 9.8 infractions by the Dartmouth team, while Dartmouth students saw an average of 4.3 infractions by the Dartmouth team. That is, the Princeton students saw more than twice as many violations by the Dartmouth team as did the Dartmouth students. Hastorf and Cantrii state, “It seems clear that the ‘game’ actually was many different games and that each version of the events that transpired was just as ‘real’ to a particular person as other versions were to other people” (p. 132).

PERCEPTION AND MASS COMMUNICATION:

So far this discussion of research has shown that perception in general is influenced by assumptions (often unconscious), cultural expectations, needs, moods, and attitudes. The same kinds of forces are at work when people respond to mass communication messages, as the following cases show.

U.S. Army TV Spots:

Mass media messages are often misunderstood. Keck and Mueller (1994) con ducted a study of U.S. Army television commercials to see whether viewers were perceiving the intended messages, and if not, what messages they were perceiving.

The study focused on two 30-second TV spots. One spot, titled “Dear Dad,” was intended to show that Army service builds personal growth, maturation, and character development, and to portray the Army as exciting, adventurous, and challenging. The second spot, titled “Basic Excellence,” portrayed basic training as a means to discover one’s ability and to overcome personal fears and inhibi­tions. The target audience for the ads was white males between 18 and 24 years of age.

A group of 396 respondents drawn from the target audience was then shown the spots and asked to fill out a questionnaire. Results showed that some of the intended messages were being perceived by the audience. For instance, 61 percent of the respondents agreed that the activities portrayed in “Basic Excellence” were exciting and challenging. Also, 68 percent agreed that a senseof personal accomplishment could be gained from engaging in the activities highlighted in the spot.

But large percentages also perceived unintended messages. For instance, 39 percent perceived that the drill sergeant was not portrayed realistically in the advertisement. And 66 percent perceived that engaging in the activities portrayed in the commercial would not lead to a good job.

There were also systematic relationships between misperceiving the ads and various characteristics of the audience. For instance, 54 percent of the black respondents felt that the drill sergeant in “Basic Excellence” was accurately portrayed, while only 26 percent of the white respondents and 32 percent of the Hispanic and Asian respondents felt that he was.

In addition, 84 percent of those with no college education thought that “Dear Dad” was a true representation of life in the Army, while only 27 percent of those with some college and 9 percent of the college grads felt that it was.

Antiprejudice Cartoons

Satire is a familiar journalistic device. It has been used in works ranging from Jonathan Swift’s Gulliver’s Travels to Garry Trudeau’s “Doonesbury” comic strip. But how is satire perceived?

The American Jewish Committee was interested in studying the effects of satire in reducing prejudice. It sponsored a study by Eunice Cooper and Marie Jahoda (1947) that investigated the effects of antiprejudice cartoons. The cartoons featured an exaggerated figure named “Mr. Biggott,” who appeared in situations designed to make prejudice appear ridiculous. For instance, one cartoon showed Mr. Biggott lying in a hospital bed and dying. He is saying to the doctor, “In case I should need a transfusion, doctor, I want to make certain I don’t get anything but blue, sixth-generation American blood!” The intention was that people looking at the cartoon would see how ridiculous prejudice is and would lessen their own feelings of prejudice.

Cooper and Jahoda tested the cartoons on 160 white, non-Jewish working- class men. About two-thirds of the sample misunderstood the cartoons. Some said the purpose of the cartoons was to legitimize prejudice. These people explained that the cartoons showed that other people had attitudes of prejudice, so the viewer should feel free to have those attitudes also. The cartoons were most likely to be understood by respondents low in prejudice and most likely to be misunderstood by respondents high in prejudice. Cooper and Jahoda suggested that fear of disapproval by a social group was one of the factors leading to this evasion of propaganda. They argued that accepting the antipreju­dice message threatened the individual’s security in groups the individual valued.

This study suggests that making fun of prejudice is not an effective way of reducing it. People tend to view satiric cartoons differently, depending on their own attitudes. Both prejudiced and unprejudiced people tended to see elements in the cartoons that confirmed their existing attitudes.

PERCEPTION OF PICTURES:

The mass media frequently employ pictures as part of messages. What do we know about how people interpret these pictures? Scott (1994) has argued that we need a theory of visual rhetoric to help us understand how people process pictures, and has offered some thoughts to move us forward in developing such a theory.

Scott suggests that much research on images in advertising has dealt with pictures either as transparent representations of reality or as conveyors of an emotional appeal. She argues for a third possibility—that pictures can act as symbols and can be used to construct rhetorical arguments. She states that visual elements are capable of representing concepts, abstractions, actions, metaphors, and modifiers, and that they can be assembled into complex arguments. Further­more, this conceptualization of images means that pictures need to be processed cognitively like other forms of information.

Scott’s article brings out three ways of thinking about pictures in the mass media—as transparent representations of reality, as conveyors of affective or emotional appeal, and as complex combinations of symbols put together to make up rhetorical arguments. Different types of pictures in the mass media may be used in these three ways to varying degrees. For instance, news photos may be higher in use as transparent representations of reality than pictures in advertisements, while pictures in advertisements may be used as parts of rhetorical arguments more than news photos. Both types of images may be at times high in conveying affective or emotional appeal (see Table 4.3).

To illustrate the rhetorical use of visual images, Scott analyzes a Clinique ad that shows tubes of lipstick and makeup immersed in a glass of soda water garnished with a slice of lime.

The image is not intended to be taken literally—the message is not that the lipstick and makeup tubes are waterproof, for instance. Scott says we can restate the message of the image in verbal terms in this way “Clinique’s new summer line of makeup is as refreshing as a tall glass of soda with a twist.” The ad is essentially a visual simile. It is an example of a visual trope, an argument presented in a figurative form in order to break through a viewer’s skepticism, boredom, or resistance.

Perceiving the Clinique ad correctly requires some rather complex informa­tion processing on the part of the perceiver. The viewer must compare two rather dissimilar things—soda water and cosmetics—and deduce what they have in common. Of several things they have in common, the correct one must be selected (“refreshing” but not “tasteless”) in order to arrive at the simile.


Relations among media influence, body image, eating concerns, and sexual orientation in men: A preliminary investigation

The current study explored the relation between sexual orientation, media persuasion, and eating and body image concerns among 78 college men (39 gay 39 straight). Participants completed measures of sexual orientation, eating disorder symptoms, appearance-related anxiety, perceived importance of physical attractiveness, perceptions of media influence, and media exposure. Gay men scored significantly higher on drive for thinness, body dissatisfaction, and body image-related anxiety than their straight counterparts. Additionally, perceptions of media influence were higher for gay men, and significantly mediated the relation between sexual orientation and eating and body image concerns. Sexual orientation also moderated the relation between perceived media influence and beliefs regarding the importance of physical attractiveness, as this relation was significant for gay men, but not straight men. The current findings suggest that gay men's increased vulnerability to media influence partially accounts for the relatively high rate of eating pathology observed in this population.


How image orientation influences perception - Psychology

While our sensory receptors are constantly collecting information from the environment, it is ultimately how we interpret that information that affects how we interact with the world. Perception refers to the way sensory information is organized, interpreted, and consciously experienced. Perception involves both bottom-up and top-down processing. Bottom-up processing refers to the fact that perceptions are built from sensory input. On the other hand, how we interpret those sensations is influenced by our available knowledge, our experiences, and our thoughts. This is called top-down processing.

One way to think of this concept is that sensation is a physical process, whereas perception is psychological. For example, upon walking into a kitchen and smelling the scent of baking cinnamon rolls, the sensation is the scent receptors detecting the odor of cinnamon, but the perception may be “Mmm, this smells like the bread Grandma used to bake when the family gathered for holidays.”

Although our perceptions are built from sensations, not all sensations result in perception. In fact, we often don’t perceive stimuli that remain relatively constant over prolonged periods of time. This is known as sensory adaptation. Imagine entering a classroom with an old analog clock. Upon first entering the room, you can hear the ticking of the clock as you begin to engage in conversation with classmates or listen to your professor greet the class, you are no longer aware of the ticking. The clock is still ticking, and that information is still affecting sensory receptors of the auditory system. The fact that you no longer perceive the sound demonstrates sensory adaptation and shows that while closely associated, sensation and perception are different.

There is another factor that affects sensation and perception: attention. Attention plays a significant role in determining what is sensed versus what is perceived. Imagine you are at a party full of music, chatter, and laughter. You get involved in an interesting conversation with a friend, and you tune out all the background noise. If someone interrupted you to ask what song had just finished playing, you would probably be unable to answer that question.

Link to Learning

See for yourself how inattentional blindness works by watching this selective attention test from Simons and Chabris (1999):

One of the most interesting demonstrations of how important attention is in determining our perception of the environment occurred in a famous study conducted by Daniel Simons and Christopher Chabris (1999). In this study, participants watched a video of people dressed in black and white passing basketballs. Participants were asked to count the number of times the team in white passed the ball. During the video, a person dressed in a black gorilla costume walks among the two teams. You would think that someone would notice the gorilla, right? Nearly half of the people who watched the video didn’t notice the gorilla at all, despite the fact that he was clearly visible for nine seconds. Because participants were so focused on the number of times the white team was passing the ball, they completely tuned out other visual information. Failure to notice something that is completely visible because of a lack of attention is called inattentional blindness.

In a similar experiment, researchers tested inattentional blindness by asking participants to observe images moving across a computer screen. They were instructed to focus on either white or black objects, disregarding the other color. When a red cross passed across the screen, about one third of subjects did not notice it (Figure 1) (Most, Simons, Scholl, & Chabris, 2000).

Link to Learning

Read more on inattentional blindness though this link to the Noba Project website.

Figure 1. Nearly one third of participants in a study did not notice that a red cross passed on the screen because their attention was focused on the black or white figures. (credit: Cory Zanker)

Motivation can also affect perception. Have you ever been expecting a really important phone call and, while taking a shower, you think you hear the phone ringing, only to discover that it is not? If so, then you have experienced how motivation to detect a meaningful stimulus can shift our ability to discriminate between a true sensory stimulus and background noise. The ability to identify a stimulus when it is embedded in a distracting background is called signal detection theory. This might also explain why a mother is awakened by a quiet murmur from her baby but not by other sounds that occur while she is asleep. Signal detection theory has practical applications, such as increasing air traffic controller accuracy. Controllers need to be able to detect planes among many signals (blips) that appear on the radar screen and follow those planes as they move through the sky. In fact, the original work of the researcher who developed signal detection theory was focused on improving the sensitivity of air traffic controllers to plane blips (Swets, 1964).

Our perceptions can also be affected by our beliefs, values, prejudices, expectations, and life experiences. As you will see later in this chapter, individuals who are deprived of the experience of binocular vision during critical periods of development have trouble perceiving depth (Fawcett, Wang, & Birch, 2005). The shared experiences of people within a given cultural context can have pronounced effects on perception. For example, Marshall Segall, Donald Campbell, and Melville Herskovits (1963) published the results of a multinational study in which they demonstrated that individuals from Western cultures were more prone to experience certain types of visual illusions than individuals from non-Western cultures, and vice versa. One such illusion that Westerners were more likely to experience was the Müller-Lyer illusion (Figure 2): The lines appear to be different lengths, but they are actually the same length.

Figure 2. In the Müller-Lyer illusion, lines appear to be different lengths although they are identical. (a) Arrows at the ends of lines may make the line on the right appear longer, although the lines are the same length. (b) When applied to a three-dimensional image, the line on the right again may appear longer although both black lines are the same length.

These perceptual differences were consistent with differences in the types of environmental features experienced on a regular basis by people in a given cultural context. People in Western cultures, for example, have a perceptual context of buildings with straight lines, what Segall’s study called a carpentered world (Segall et al., 1966). In contrast, people from certain non-Western cultures with an uncarpentered view, such as the Zulu of South Africa, whose villages are made up of round huts arranged in circles, are less susceptible to this illusion (Segall et al., 1999). It is not just vision that is affected by cultural factors. Indeed, research has demonstrated that the ability to identify an odor, and rate its pleasantness and its intensity, varies cross-culturally (Ayabe-Kanamura, Saito, Distel, Martínez-Gómez, & Hudson, 1998).

Children described as thrill seekers are more likely to show taste preferences for intense sour flavors (Liem, Westerbeek, Wolterink, Kok, & de Graaf, 2004), which suggests that basic aspects of personality might affect perception. Furthermore, individuals who hold positive attitudes toward reduced-fat foods are more likely to rate foods labeled as reduced fat as tasting better than people who have less positive attitudes about these products (Aaron, Mela, & Evans, 1994).

Link to Learning

Review the differences between sensation and perception in this CrashCourse Psychology video.

Think It Over

1. Think about a time when you failed to notice something around you because your attention was focused elsewhere. If someone pointed it out, were you surprised that you hadn’t noticed it right away?


Watch the video: Κρύων Πέντε Έννοιες για το Νέο Άνθρωπο. Five Concepts for the New Human (August 2022).