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Perceptual Interpretation
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MODULE OVERVIEW
Sensory Deprivation and Restored Vision
(pp.250-251)
Module 17 explores how we interpret our sensations
into meaningful perceptions. It deals with two important issues. The first issue is the role of experience, as
opposed to heredity, in perception. Make sure you
understand the results of studies of recovery from
blindness, early sensory restriction, adaptation to distorted environments, and perceptual set. The second
is the possible existence of ESP, or perception without
sensation. You should be able to discuss both the
claims made for ESP and the criticisms of these
claims.
Human factors psychologists study the interaction of people and machines and try to find ways to
increase safety and productivity.
NOTE: Answer guidelines for all Module 17 questions begin on page 201.
MODULE REVIEW
First, skim each section, noting headings and boldface
items. After you have read the section, review each
objective by answering the fill-in and essay-type
questions that follow it. As you proceed, evaluate
your performance by consulting the answers on page
201. Do not continue with the next section until you
understand each answer. If you need to, review or
reread the section in the textbook before continuing.
David Myers at times uses idioms that are unfamiliar to some readers. If you do not know
the meaning of the following words in the context in which they appear in the text, refer to
page 203 for an explanation: Ping-Pong ball.
Objective 17-1:Describe the contribution of restoredvision and sensory deprivation research in our understanding of the nature-nurture interplay in our perceptions.
1. The idea that knowledge comes from inborn
ways of organizing sensory experiences was proposed by the philosopher
_
2. On the other side were philosophers who maintained that we learn to perceive the world by
experiencing it. One philosopher of this school
was
_
3. Studies of cases in which vision has been restored
to a person who was blind from birth show that,
upon seeing tactilely familiar objects for the first
time, the person
(can/cannot) recognize them.
4. Studies of sensory deprivation demonstrate that
visual experiences during
_
are crucial for perceptual development. Such
experiences suggest that there is a
_________________
for
normal sensory and perceptual development. For
this reason, human infants born with an opaque
lens, called a
, typically
have corrective surgery right away.
197
r
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Module 17 Perceptual Interpretation
Objective 17-4: Explain why the same stimulus can
evoke different perceptions in different contexts.
Perceptual Adaptation (pp. 251-252)
If you do not know the meaning of any of the
following words in the context in which they
appear in the text, refer to page 203 for an
explanation: we may feel slightly disoriented, even
dizzy.
Objective 17-2: Explain how the research on distorting goggles increases our understanding of the
adaptability of perception.
4. How a stimulus is perceived depends on our perceptual schemas and the
_
in which it is experienced.
5. The context of a stimulus creates a
_______
(top-down/bottom-up)
expectation that influences our perception as we
match our
(top-down/bottom-up) signal against it.
6. Our perception is also influenced by
1. Humans given glasses that shift or invert the
visual field.
(will/will not)
adapt to the distorted perception. This is called
________
________
about gender and the
context of our experiences.
Perception and Human Factor (pp. 256-258)
2. Animals such as chicks
_
(adapt/ do not adapt) to distorting lenses.
3. When distorting goggles are first removed, most
people experience a brief perceptual
________
, as their perceptual systems
continue to compensate for the shifted visual
input.
Perceptual Set (pp. 252-256)
Objective 17-5: Describe the role human factors
psychologists play in creating user-friendly machines
and work settings.
1. Psychologists who study the importance of con-
sidering perceptual principles in the design of
machines, appliances, and work settings are
called
_
________
psychologists.
2. Victims of the "curse of knowledge," technology
If you do not know the meaning of any of the
following words, phrases, or expressions in the
context in which they appear in the text, refer
to page 203 for an explanation: to see is to believe
... to believe is to see; a "monster" in Scotland's
Loch Ness;from what's behind our eyes and
between our ears; in the eyes of their beholders.
Objective 17-3: Define perceptual set, and explain
how it influences what we do or do not perceive.
developers who assume that others share their
_________
, may create designs that
are unclear to others.
3. Another example of failure to consider the
human factor in design is the
technology that provides embarrassing headsets
that amplify sound for people with hearing loss.
Is There Extrasensory Perception? (pp. 258-262)
1. A mental predisposition that influences percep-
tion is called a
_
2. Through experience, people acquire perceptual
________
, as reflected in children's
drawings at different ages. This explains why we
more accurately recognize
_
of famous faces than these people's actual faces.
3. Our face recognition is especially attuned to the
expressive areas of the
and
If you do not know the meaning of any of the
following words, phrases, or expressions in the
context in which they appear in the text, refer
to pages 203-204 for an explanation: uncanny;
mind-blowing performance; unsatisfied hunger ...
an itch.
Progress Test
Objective 17-6:Identify the three most testable forms
of ESP, and explain why most research psychologists
remain skeptical of ESP claims.
1. Perception outside the range of normal sensation
is called
_
2. Psychologists who study ESP are called
3. The form of ESP in which people claim to be
capable of reading others' minds is called
_________
. A person who "senses"
that a friend is in danger might claim to have the
ESP ability of
. An ability to
"see" into the future is called
_________
. A person who claims to be
able to levitate and move objects is claiming the
powerof
_
4. Analyses of psychic visions and premonitions
reveal
(high/ chance-level)
accuracy. Nevertheless, some people continue to
believe in their accuracy because vague predictions often are later
to match
events that have already occurred. In addition,
people are more likely to recall or
________
dreams that seem to have
come true.
5. Critics point out that a major difficulty for parapsychology is that ESP phenomena are not consistently
_
6. Researchers who tried to reduce external distractions between a "sender" and a "receiver" in an
ESP experiment reported performance levels that
________
(beat/ did not beat) chance
levels. More recent studies
_
(failed to replicate the results/found equally high
levels of performance).
PROGRESS TEST
Multiple-Choice Questions
Circle your answers to the following questions and
check them with the answers beginning on page 201.
If your answer is incorrect, read the explanation for
why it is incorrect and then consult the appropriate
pages of the text.
199
1. A person claiming to be able to read another's
mind is claiming to have the ESP ability of:
a. psychokinesis.
c. clairvoyance.
b. precognition.
d. telepathy.
2. Which philosopher maintained that knowledge
comes from inborn ways of organizing our sensoryexperiences?
c. Stratton
a. Locke
d. Norman
b. Kant
3. Dr. Martin is using natural mapping to redesign
the instrument gauges of automobiles to be more
"user friendly." Dr. Martin is evidently a(n):
a. psychophysicist.
b. cognitive psychologist.
c. human factors psychologist.
d. experimental psychologist.
4. Kittens and monkeys reared seeing only diffuse,
unpatterned light:
a. later had difficulty distinguishing color and
brightness.
b. later had difficulty perceiving color and
brightness, but eventually regained normal
sensitivity.
c. later had difficulty perceiving the shape of
objects.
d. showed no impairment in perception, indicating that neural feature detectors develop even
in the absence of normal sensory experiences.
5. Adults who are born blind but later have their
vision restored:
a. are almost immediately able to recognize
familiar objects.
b. typically fail to recognize familiar objects.
c. are unable to follow moving objects with their
eyes.
d. have excellent eye-hand coordination.
6. Which of the following influences perception?
a. biological maturation
b. the context in which stimuli are perceived
c. expectations
d. all of the above
7. Jack claims that he often has dreams that predict
future events. He claims to have the power of:
a. telepathy.
c. precognition.
b. clairvoyance.
d. psychokinesis.
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Module 17 Perceptual Interpretation
8. Researchers who investigated telepathy found
that:
a. when external distractions are reduced, both
the "sender" and the "receiver" become much
more accurate in demonstrating ESP.
b. only "senders" become much more accurate.
c. only "receivers" become much more accurate.
d. over many studies, none of the above occur.
9. Experiments with distorted visual environments
demonstrate that:
a. adaptation rarely takes place.
b. animals adapt readily, but humans do not.
c. humans adapt readily, while lower animals
typically do not.
d. adaptation is possible during a critical period
in infancy but not thereafter.
10. The phenomenon that refers to the ways in which
an individual's expectations influence perception
is called:
a. perceptual set.
b. perceptual adaptation.
c. clairvoyance.
d. telekinesis.
11. Thanks to
, TiVo and DVR have solved
the TV recording problem caused by the complexity of VCRs.
a. parapsychologists
b. human factors psychologists
c. psychokineticists
d. Gestalt psychologists
12. According to the philosopher
to perceive the world.
a. Locke
c. Stratton
b. Kant
d. Norman
, we learn
13. Which of the following statements best describes
the effects of sensory restriction?
a. It produces functional blindness when experienced for any length of time at any age.
b. It has greater effects on humans than on animals.
c. It has more damaging effects when experienced during infancy.
d. It has greater effects on adults than on children.
14. Psychologists who study ESP are called:
a. clairvoyants.
c. parapsychologists.
b. telepaths.
d. levitators.
15. Which of the following statements concerning
ESP is true?
a. Most ESP researchers are quacks.
b. There have been a large number of reliable
demonstrations of ESP.
c. Most research psychologists are skeptical of
the claims of defenders of ESP.
d. There have been reliable laboratory demonstrations of ESP, but the results are no different from those that would occur by chance.
16. Although carpenter Smith perceived a briefly
viewed object as a screwdriver, police officer
Wesson perceived the same object as a knife. This
illustrates that perception is guided by:
a. psychokinetics.
b. perceptual adaptation.
c. critical periods.
d. perceptual set.
17. Regina claims that she can bend spoons, levitate
furniture, and perform many other "mind over
matter" feats. Regina apparently believes she has
the power of:
a. telepathy.
c. precognition.
b. clairvoyance.
d. psychokinesis.
18. The predictions of leading psychics are:
a. often ambiguous prophecies later interpreted
to match actual events.
b. no more accurate than guesses made by
others.
c. nearly always inaccurate.
d. all of the above.
True-False Items
Indicate whether each statement is true or false by
placing Tor F in the blank next to the item.
1. Laboratory experiments have laid to
rest all criticisms of ESP.
2. Unlike other animals, humans have no
critical period for visual stimulation.
3. Immanuel Kant argued that experience
determined how we perceive the world.
4. After a period of time, humans are able
to adjust to living in a world made
upside down by distorting goggles.
S. Perception is influenced by psychological factors such as set and expectation as
well as by physiological events.
6. John Locke argued that perception is
inborn.
Answers
201
KEY TERMS
3. telepathy; clairvoyance; precognition; psychokinesis
Using your own words, on a separate piece of paper
write a brief definition or explanation of each of the
following terms.
4. chance-level; interpreted (retrofitted); reconstruct
S. reproducible
6. beat; failed to replicate the results
1. perceptual adaptation
2. perceptual set
3. human factors psychology
4. extrasensory perception (ESP)
S. parapsychology
ANSWERS
Module Review
Sensory Deprivation and Restored Vision
1. Kant
2. Locke
3. cannot
4. infancy; critical period; cataract
Perceptual Adaptation
1. will; perceptual adaptation
2. do not adapt
3. aftereffect
Perceptual Set
1. perceptual set
2. schemas; caricatures
3. eyes; mouth
4. context
S. top-down; bottom-up
6. stereotypes; emotional
Perception and the Human Factor
Progress Test
Multiple-Choice
Questions
1. d. is the answer.
a. Psychokinesis refers to the claimed ability to
perform acts of "mind over matter."
b. Precognition refers to the claimed ability to
perceive future events.
c. Clairvoyance refers to the claimed ability to
perceive remote events.
2. b. is the answer.
a. Locke argued that knowledge is not inborn but
comes through learning.
c. Stratton experimented with distorting goggles.
d. Norman hosts a Web site on designing equipment for people.
3. c. is the answer.
4. c. is the answer.
a. & b. The kittens had difficulty only with lines
they had never experienced, and never regained
normal sensitivity.
d. Both perceptual and feature-detector impairment resulted from visual deprivation.
S. b. is the answer. Because they have not had early
visual experiences, these adults typically have
difficulty learning to perceive objects.
a. Such patients typically could not visually recognize objects with which they were familiar by
touch, and in some cases this inability persisted.
c. Being able to perceive figure-ground relationships, patients are able to follow moving objects
with their eyes.
d. This answer is incorrect because eye-hand
coordination is an acquired skill and requires
much practice.
6. d. is the answer.
1. human factors
2. expertise
3. assistive listening
Is There Extrasensory Perception?
1. extrasensory perception
2. parapsychologists
7. c. is the answer.
a. This answer would be correct had Jack claimed
to be able to read someone else's mind.
b. This answer would be correct had Jack claimed
to be able to sense remote events, such as a friend
in distress.
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Module 17 Perceptual Interpretation
d. This answer would be correct had Jack claimed
to be able to levitate objects or bend spoons without applying any physical force.
8. d. is the answer.
9. c. is the answer. Humans and certain animals,
such as monkeys, are able to adjust to upsidedown worlds and other visual distortions, figuring out the relationship between the perceived
and the actual reality; lower animals, such as
chickens and fish, are typically unable to adapt.
a. Humans and certain animals are able to adapt
quite well to distorted visual environments (and
then to readapt).
b. This answer is incorrect because humans are
the most adaptable of creatures.
d. Humans are able to adapt at any age to distorted visual environments.
10. a. is the answer.
b. Retinal disparity is a binocular depth cue based
on the fact that each eye receives a slightly different view of the world.
c. Convergence is a binocular depth cue based on
the fact that the eyes swing inward to focus on
near objects.
d. Visual capture refers to the tendency of vision
to dominate the other senses.
11. b. is the answer.
a. Parapsychologists study claims of ESP.
c. Psychokineticists are people who claim ESP has
the power of "mind over matter."
d. Gestalt psychologists emphasize the organization of sensations into meaningful perceptions.
12. a. is the answer.
b. Kant claimed that knowledge is inborn.
c. Stratton experimented with distorting goggles.
d. Norman hosts a Web site on designing equipment for people.
13. c. is the answer. There appears to be a critical
period for perceptual development, in that sensory restriction has severe, even permanently, disruptive effects when it occurs in infancy but not
when it occurs later in life.
a. & d. Sensory restriction does not have the same
effects at all ages, and it is more damaging to children than to adults. This is because there is a critical period for perceptual development; whether
functional blindness will result depends in part
on the nature of the sensory restriction.
b. Research studies have not indicated that sensory restriction is more damaging to humans than
to animals.
14. c. is the answer.
a., b., & d. These psychics claim to exhibit the
phenomena studied by parapsychologists.
15. c. is the answer.
a. Many ESP researchers are sincere, reputable
researchers.
b. & d. There have been no reliable demonstrations of ESP.
16. d. is the answer. The two people interpreted a
briefly perceived object in terms of their perceptual sets, or mental predispositions, in this case
conditioned by their work experiences.
a. Both Smith and Wesson had the same sensory
experience of the object, so linear perspective
cues would not cause their differing perceptions.
b. Shape constancy refers to the perception that
objects remain constant in shape even when our
retinal images of them change.
c. Retinal disparity is a binocular depth cue; it has
nothing to do with individual differences in perception.
17. d. is the answer.
a. Telepathy is the claimed ability to "read"
minds.
b. Clairvoyance refers to the claimed ability to
perceive remote events.
c. Precognition refers to the claimed ability to
perceive future events.
18. d. is the answer.
True-False Items
1. F
2. F
3. F
4. T
S. T
6. F
Key Terms
1. Perceptual adaptation refers to our ability to
adjust to an artificially displaced or even inverted
visual field. Given distorting lenses, we perceive
things accordingly but soon adjust by learning
the relationship between our distorted perceptions and the reality.
2. Perceptual set is a mental predisposition to perceive one thing and not another.
3. Human factors psychology explores how people
and machines interact and how machines and
physical environments can be adapted to human
behaviors and thus to increase safety and productivity.
Focus on Vocabulary and Language
4. Extrasensory perception (ESP) refers to the controversial claim that perception can occur without
sensory input. Supposed ESP powers include
telepathy, clairvoyance, and precognition.
Memory aid: Extra- means "beyond" or "in addition to"; extrasensory perception is perception
outside or beyond the normal senses.
FOCUS ON VOCABULARY AND LANGUAGE
Sensory Deprivation and Restored Vision
Most had been born with cataracts- clouded lenses
that allowed them to see only diffused light, rather
as you or I might see a diffuse fog through a PingPong ball sliced in half. People born with cataracts
cannot see clearly because the normally transparent
lenses in their eyes are opaque. To understand what
their vision is like, imagine what you would see if
you had your eyes covered with half of a small,
white, plastic ball that is used in table tennis (PingPong). When cataract patients have their vision
restored, after being blind since birth, they can sense
colors and distinguish figure from ground (innate
capacities), but they cannot visually recognize things
that were familiar by touch.
Perceptual Adaptation
Given a new pair of glasses, we may feel slightly disoriented, even dizzy. When we start wearing ordinary
eyeglasses or when we are fitted with a new pair,
our initial reaction is a little confusion and vertigo
(dizziness). However, we quickly adapt within a few
days. We can also adapt to lenses that distort what
we are looking at by 40° to one side, and even to distortion lenses that invert reality (turn the visual
image upside down-a topsy-turvy world). Fish,
frogs, salamanders, and young chickens cannot
adapt in this way.
Perceptual Set
As everyone knows, to see is to believe. As we also
know, but less fully appreciate, to believe is to see. The
expression "seeing is believing" means that we put
much reliance on visual information when deciding
(believing) what is true. Myers shows us that, on the
contrary, what we believe may actually affect what
we see. Our assumptions, expectations, and mental
203
S. Parapsychology is the study of ESP, psychokinesis, and other paranormal forms of interaction
between the individual and the environment.
Memory aid: Para-, like extra-, indicates "beyond";
thus, paranormal is beyond the normal and parapsychology is the study of phenomena beyond
the realm of psychology and known natural laws.
predispositions (perceptual sets) determine, to a
large extent, our perceptions.
In 1972, a British newspaper published genuine,
unretouched photographs of a "monster"
in
Scotland's Loch Ness ....
People who had heard
about, or believed in, the Loch Ness Monster before
seeing a very ambiguous picture of a log were more
inclined to see what they expected to see (i.e., a
monster) because of their perceptual set.
Clearly, much of what we perceive comes not just
from the world "out there" but also from what's
behind our eyes and between our ears. Myers is reiterating the point that our mental predispositions, expectations, beliefs, etc. (what's behind our eyes and between
our ears) influence much more of what we perceive
than the sensory stimulation received from the outside world.
Some differences, it seems, exist merely in the eyes of their
beholders. The familiar saying "beauty is in the eye of
the beholder" means that what is perceived as beautiful has more to do with what the perceiver subjectively believes than with the absolute qualities of the
person or object being judged. Likewise, our stereotypes (rigid, conventional ideas or beliefs) about
gender or culture can greatly influence (color) what
is perceived.
Is There Extrasensory Perception?
... uncanny ... People who have dreams that coincide, by pure chance, with later events often have an
eerie or strange (uncanny) feeling about the accuracy
of their apparent precognitions.
. . . mind-blowing performances. Some alleged (socalled) psychics, using magic tricks and not extrasensory ability, unethically manipulate and deceive
(exploit) gullible (unquestioning)
audiences with
impressive and wondrous demonstrations (mindblowing performances). As Myers points out, after
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Module 17 Perceptual Interpretation
many, many years of investigation and thousands of
experiments there is no scientific evidence that
extrasensory abilities exist (believers in the paranormal need only produce one person who can demonstrate a single, reproducible ESP phenomenon to
refute the claim that there is no ESP-this has not
happened).
But some people also have an unsatisfied hunger for
wonderment, an itch to experience the magical.
Some people are predisposed to believe in ESP
because they have a deeply felt need (unsatisfied
hunger) for surprise and amazement and a strong
ambition or desire (an itch) to explore the mysterious
and unknown.