Сборник текстов по психологии для чтения на английском языке с упражнениями Г.В. Бочарова, М.Г. Степанова

patients continue to feel vividly the presence of the missing arm, a phenomenon termed phantom limb in the late 1800s by physician and author Silas Wier Mitchell. Many people report that their phantom limb is frozen, paralyzed in a constant or fixed position, and that this is sometimes painful.

We wondered whether touch sensations in the phantom arm could be influenced by visual input. We positioned a mirror on the table in front of a patient, along his midline, and asked him to position his intact arm and stump/phantom hand symmetrically on either side of the mirror. When he looked at the reflection of his normal hand in the mirror, he experienced the phantom being visually resurrected. Remarkably, if the patient moved his normal hand while looking at its reflection in the mirror, the previously frozen phantom seemed to become animated; he not only saw the hand, but also felt it move. In some cases, this sensation seemed to alleviate the pain associated with the phantom.

The visual capture effect also indicates our need for a single, sensible narrative of the world. That is, we (our brains) tend to reinterpret or discard some information, even when doing so may produce errors or illusions. This influence of vision has resulted in a kind of vision chauvinism in research, leasing scientists to pay less attention to the other senses.

Touched in the Head?

The neural basis of these intermodality illusions has not been studied in detail. Recent work by Krish Sathian of Emory University and Alvaro Pasquel Leone of Harvard University suggests that somatosensory signals (those having to do with touch) may be seen in the primary visual cortex under certain circumstances — for example, in blind Braille readers. The tactile signals processed in the somatosensory centers of the brain may actually send feedback all the way to the very early stages of visual processing, instead of being merely combined at some higher level. Studies on visual capture suggest that the converse may also be true — namely, that visual input may project to what is traditionally considered primary somatosensory cortex. These inter actions between the senses, in addition to informing us about brain

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mechanisms for information processing, may also provide a useful tool for rehabilitation for neurological disorders.

We would like to consider here some tactile illusions that bear a striking similarity to visual illusions. Try the following experiment. Place two coins in your freezer till they are chilled (maybe 20 minutes). Remove them and place them on a table flanking a similar coin that has been kept at room temperature, so that the three coins now form a row. Now place the tips of the index and ring finger of one hand on the two cold coins and the middle finger on the middle coin. Amazingly, the middle finger feels equally cold. Perhaps temperature sensing pathways of the brain simply do not have the resolving power to discern two discreet sources. Yet the middle finger does not feel cold unless it is in contact with a neutral coin; if there are no tactile sensations emerging from it, the brain is reluctant to “fill in,” or ascribe cold to, this region.

But how “clever” is this filling in mechanism? What if the middle finger pressed against velvet or sandpaper rather than a coin? Does it have to be similar to what is being touched by the index and ring fingers? If so, how similar? And does this interpolation of cold occur early in sensory processing — for example, in the spinal cord or thalamus (the “gateway” for sensory inputs to the brain)? Or does it happen “higher up” in later processing staged in the brain?

One way to find out is to see what happens if you simply bend the middle finger upward and then put the middle finger of the other hand in its place. The illusion now disappears, suggesting that the filling in occurs at an early stage of tactile information processing, not at the higher level of space representation in the brain. (We know this occurs at an early stage because the sensory signals from two hands project to two separate hemispheres in the brain; information from them can be compared only at a relatively late stage of processing.)

Let us try something different. Cross your left middle finger over your left index finger, making a small V at the end. Now place the V formed by the fingers on the nose. Astonishingly, many people who perform this “Aristotle Illusion” maneuver report a distinct feeling of having two noses! How is this effect possible?

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One way to interpret the phenomenon is to realize that given the normal, habitual spatial arrangement of the fingers, the only way the left side of your left middle finger will be stimulated simultaneously with the right side of your left index finger is when they are touching two objects. So the brain interprets the tactile experience as “I must have two noses.” According to psychologists Stuart Anstis of The University of California, San Diego, the nose is not the only appendage in which perceptual doubling can be produced.

Jelly or Velvet

The following demonstration may be a related effect. Get some coarse chicken cage mesh, preferably mounted in a wooden frame. Then hold the mesh between the palms of your hands. Nothing peculiar so far. Now start rubbing your palms against each other with the wire between them. Remarkably, your palms will feel like jelly or velvet. The cause of this striking illusion has yet to be determined. One possibility is that it has something to do with sensing and signaling the contrast between the sharp wire and the “neutral” touch sensations on the skin — the opposite of sharp being velvety or jellylike. A version of this illusion can be found in many science museums.

You can even get your hands to “float” — a well known trick, sometimes called the Kohnstamm effect, reintroduced to us by our 11 year old son, Jayakrishnan Ramachandran. Stand in the middle of an open doorway and use your arms to apply outward pressure on the two sides as if you were pushing them away from your body. After about 40 seconds, suddenly let go and relax, stand normally and just let your arms hang by your sides. If you are like most of us, your arms will involuntarily rise up as if pulled by two invisible helium balloons. The reason? When you apply continuous outward force, your brain gets used to this as the “neutral state”, so that when the pressure suddenly disappears, your arms drift outward.

This simple demonstration shows that the sensory areas of your brain are not the passive recipients of signals from your sense organs. Instead we should think of them as being in a state of dynamic equilibrium with the outside world, an equilibrium point that is constantly shifting in response to a changing environment.

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I. Choose the word from the box to match the definition on the left.

2.Area of the brain that processes in ______________________

coming signals from the skin, muscles, and bones.

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sented stimuli so that what is per ceived does not correspond to physical reality.

II. Answer the questions to the text.

1.What part of the brain is devoted to visual processing?

2.In what case may visual dominance cause us to actually feel things differently?

3.How does vision influence touch?

4.What is meant by a phenomenon termed phantom limb?

5.What do studies on “visual capture” suggest?

6.Are tactile and visual illusions similar?

7.What does the filling in mechanism mean?

8.At what stage of tactile information processing does the filling in mechanism occur?

9.How may Aristotle Illusion be defined?

10.What is the Kohnstamm effect?

11.The sensory areas of your brain are in a state of dynamic equilibrium with the outside world, aren’t they?

III.Choose the facts to prove that:

1.Vision influences touch.

2.The sensory areas of the brain are not the passive recipients of signals from the sense organs.

T e x t 18

SNAP JUDGMENTS

Initial encounters are emotionally concentrated events that can overwhelm us — even convince us that the room is spinning. We walk away from them with a first impression that is like a Polaroid picture — a head to toe image that develops instantly and never entirely fades. Often, that snapshot captures important elements of the truth.

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Consider one study in which untrained subjects were shown 20 to 32 second videotaped segments of job applicants greeting inter viewers.The subjects then rated the applicants on attributes such as self assurance and likability. Surprisingly, their assessments were very close to those of trained interviewers who spent at least 20 minutes with each applicant. What semblance of a person — one with a distinct appearance, history and complex personality — could have been captured in such a fleeting moment?

The answer lies in part in how the brain takes first impression Polaroids — creating a composite of all the signals given off by a new experience. Psychologists agree that snap judgments are a holistic phenomenon in which clues (mellifluous voice, Rolex watch, soggy handshake, hunched shoulders) hit us all at once and form an impres sion larger than their sum.

We do search for one particular sign on a new face: a smile. “We can pick up a smile from 30 meters away,” says Paul Ekman, professor of psychology at the University of California Medical School in San Francisco, and a pioneer of research on facial expressions. “A smile lets us know that we’re likely to get a positive reception, and it’s hard not to reciprocate.”

By the time we flash that return grin, our Polaroid shutter will have already closed. Just three seconds are sufficient to make a conclusion about fresh acquaintances. Nalini Ambady, professor of psychology at Tufts University in Medford, Massachusetts, studies first impressions carved from brief exposure to another person’s behavior, what she calls “thin slices” of experience. She says humans have developed the ability to quickly decide whether a new person will hurt or enrich us — judgments that had lifesaving ramifications in an earlier era.

She believes that thin slices are generated in the most primitive area of the brain, where feelings are also processed, which accounts for the emotional punch of some first encounters. Immediate distrust of a certain car salesman of affinity for a prospective roommate originates in the deepest corners of the mind.

The ability to interpret thin slices evolved as a way for our ancestors to protect themselves in an eat or beaten world, whereas modern day threats to survival often come in the form of paperwork (dwindling stock portfolios) or intricate social rituals (impending divorce). The

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degree to which thin slices of experience help us navigate modern encounters — from hitchhikers to blind dates — is up for debate.

Ekman says that people excel at reading facial expressions quickly, but only when a countenance is genuine. Most people cannot tell if someone is feigning an emotion, he says, “unless their eyes have been trained to spot very subtle expressions that leak through.” Consider anger: When we are boiling mad, our lips narrow — an expression we can’t make on demand when we’re pretending.

And the accuracy of a snap judgment always depends on what exactly we’re sizing up. Ekman doesn’t think we can use a thin slice of behavior to judge, say, if someone is smart enough to be our study partner or generous enough to lend us a bus token. “But we can pretty easily distinguish one emotion from another, particularly if it’s on the face for a second or more.” “Spending more time with a genuine person”, he says, “won’t yield a more accurate sense of that person’s emotional state.”

First impressions are not merely hard wired reactions — we are also taught how to judge others, holding our thin slices up to the light of social stereotypes. Brian Nosek, professor of psychology at the University of Virginia, studies the implicit attitudes that enter into our calculations. Just because someone carries an ACLU membership card or makes a point to invite their senior citizen friends to dance club outings doesn’t mean they don’t have prejudices bubbling under the surface. Nosek and colleagues administer a quick online test that reveals the beliefs people either can’t or won’t report.

Called the Implicit Association Test, it asks participants to pair concepts, such as “young” with “good” or “elderly” with “good”. If, in some part of his mind, “old” is more closely related to “bad” than to “good”, the test taker will respond more quickly to the first pairing of words than to the second. In versions of these tests, small differences in response times are used to determine if someone is biased toward youth over the elderly, African Americans over Caucasians or for President Bush over President Kennedy. “When I took the test,” says Nosek, “I showed a bias toward whites. I was shocked. We call it unconsciousness raising, in contrast to the consciousness raising of the 1960s.”

As subtle as implicit attitudes are, they can cause serious real world damage. If an angry person stumbles upon someone of a different race or religion, he is likely to perceive that person negatively, according to

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recent research. Anger incites instinctive prejudiced responses toward “outsiders,” a finding that has important implications for people in law enforcement and security.

Certain physical features consistently prompt our brains to take first impression Polaroids with a distorting filter. People who have a “baby face,” characterized by a round shape, large eyes and small nose and chin, give off the impression of trustworthiness and naivete´ — on average, a false assumption. A pretty face also leads us astray: Our tendency is to perceive beautiful people as healthier and just plain better than others.

Lueslie Zebrowitz, professor of psychology at Brandeis University in Massachusetts, argues that we overgeneralize in the presence of baby mugs and homely visages. Humans are hardwired to recognize a baby as an innocent, weak creature who requires protection. By the same token, mating with someone who is severely deformed, and thereby unattractive, may keep your DNA from spreading far and wide. But we overgeneralize these potentially helpful built in responses, coddling adults with babyish miens who in fact don’t need our care and shinning unattractive people who may not meet our standards of beauty but certainly don’t pose an imminent threat to our gene pool.

Zebrowitz has found that many baby faced grown ups, particularly young men, overcompensate for misperceptions by cultivating tougher than average personalities in an attempt to ward off cheek pinching aunts. Think of the sweet faced rapper Eminem, who never cracks a smile, or the supermodel juggling, hard partying actor Leonardo DiCaprio.

Not every observer is equally likely to draw unwarranted conclusions about a smooth cheeked man or a woman with stunning, symmetrical features. People who spend time cultivating relationships are more likely to make accurate snap judgments.

“A good judge of personality isn’t just someone who is smarter — it’s someone who gets out and spends time with people,” says David Funder, a professor of psychology at the University of California at Riverside, who believes in the overall accuracy of snap judgments. Funder has found that two observers often reach a consensus about a third person, and the assessment of himself. “We’re often fooled, of course, but we’re more often right.”

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On the other side of the equation, some people are simpler to capture at first glance than others. “The people who are easiest to judge are the most mentally healthy,” says Randy Colvin, associate professor of psychology at Northeastern University in Boston. “With mentally healthy individuals,” Colvin theorizes, “exterior behavior mimics their internal views of themselves. What you see is what you get.”

I. Choose the word from the box to match the definition on the left.

groups of persons distinguishable from each other by a factor which, in principle, should be irrelevant to the test.

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6. The process by which one integra ______________________

tes various sources of information about another into an overall judgement.

II.Answer the questions to the text.

1.What are initial encounters like?

2.How does the brain take the first impressions?

3.How does Nalidy Ambady, professor of psychology at Tufts University, interpret first impressions?

4.What does the accuracy of a snap judgement depend on?

5.What is the Implicit Association Test aimed at?

6.What can cause serious real world damage?

7.What kinds of faces may lead us astray?

8.Who is considered to be a good judge of personality according to David Funder’s opinion?

9.What kind of people are the easiest to judge?

III.Choose the facts to prove that

1.People excel at reading facial expressions quickly, but only when a countenance is genuine.

2.As subtle as implicit attitudes are, they can cause serious real world damage.

3.People who spent time cultivating relationships are more likely to make accurate snap judgements.

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