Pavlov State Medical University of St. Petersburg Department of Psychiatry Psychology, part 1, course for foreign students St. Petersburg 2003 The text of this course is compiled by assistants V.R. Piotrovskaia M.D., Ph.D., E.R. Isaeva, Ph.D. and professor V.I. Krylov, the Department of Psychiatry of Pavlov State Medical University of St. Petersburg. Editor: professor N.G.Neznanov. Reviser: T.V. Sokolovskaia, Dr. of Psychology, reader at the Department of Medical Psychology of St. Petersburg Medical Academy of Postgraduate Education. The Contents:
Theme 1. Psychology, its subfields, approaches and methods.The main topics: 1.The subfields of psychology. 2.Biological, psychodynamic, humanistic, cognitive and behavioral approaches. 3.The main goals of research in psychology. 4. Some research methods. Psychology is the science of behavior and mental processes. This means that psychologists use the methods
of science to investigate all kinds of behavior and mental processes,
from the activity of a single nerve cell to the social conflicts in a
complex society, from the development of language in childhood to the
adjustments required in old age. Like
other sciences, psychology has developed numerous subfields or areas of
specialization. This subfields approach behavior and mental processes
in somewhat different ways. Biological psychology In
compliance with Bernstein D.A. “psychologists who analyze the
biological factors in behavior and mental processes are called
biological psychologists. Some biological psychologists explore the
chemical interactions within and between nerve cells, especially in the
brain and spinal cord. Some
researchers explore the relationships between brain activity and
behavior. For example, they might map the parts of the brain that
become activated when people solve problems or confront unexpected
events. Other biological psychologists look for reasons to how hormones influence emotions and behavior”. Experimental and cognitive psychology. Wilhelm Wundt, William James, Edward Titchener, and other early psychologists used the term experimental
to distinguish their experiments on human perception, learning and
memory, from attempts of philosophers and others who thought hard about
such phenomena but performed no experiments. The scientific methods of
experimental psychology are now evident in research in every subfield
of psychology. Cognitive psychologists
aim their research toward ever more detailed analysis of mental
processes involved in learning, memory and perception. They explore the
processes underlying judgment, decision making, problem solving,
imagination and other aspects of complex human thought or cognition. Personality psychology Personality
psychologists focus on the characteristics that make us unique. They
also try to identify the specific ways in which people differ , to
explore the relationships between people’s personalities and their
tendency to think, act and feel in certain ways. Social psychology The
topics studied by social psychologists are: social perception and
impression formation, aggression, the formation and change of
attitudes, sex roles, and conformity, and social influence. Clinical psychology. Clinical
psychologists, using tests, interviews and observation, seek to
understand and correct abnormal functioning. They study typical alterations
of perception, thinking, memory, attention, emotions in the cases of
mental disorders and internal diseases. They use similar methods to
pinpoint emotional conflicts and adjustment problems and offer individual
correction to help solve those problems. The clinician psychology may
conduct psychotherapy in private practice or in hospitals, prisons, or
institutions for mental retarded persons. Developmental psychology Developmental
psychologists describe those changes, trying to understand their causes
and exploring their effects. They have conducted research on the stress
of adolescence and the changes with old age. But because changes in
language, thinking, social skills, and personality occur most
dramatically in infancy and childhood, much developmental research has
focused on those early stages of life. Other research has helped launch
special educational programs for preschoolers who appear likely to be
at a disadvantage when they start school. Quantitative psychology. Quantitative , or measurement psychologists develop and apply mathematical methods for summarizing and analyzing data. They
have helped biological psychologists find precise mathematical ways of
describing the changes in a subjects mental processes .Some of these
methods are known as statistical analyses. Quantitative psychologists are
also involved in constructing and evaluating paper-and-pencil tests
used to measure traits, attitudes, mental capacity, and mental
disorders.
Psychological Approaches.The biological approach This
approach begins with the assumption that biological factors, such as
genetics, electrical and chemical activity in the brain, and the
actions of hormones are the most important determinants of behavior and
mental processes. Those who adopt this approach study emotions, mental
disorders, memory, thinking, and other psychological phenomena by
seeking out and learning about their biological components. The psychodynamic approach The psychodynamic approach was founded by Sigmund Freud. The psychodynamic approach
presumes that behavior and mental processes reflect constant, dynamic,
and often unconscious struggles within each person. These struggles are
varied and complex, thus they usually involve conflict between the
impulse to satisfy instincts or wishes (for food, sex, or aggression,
for example) and the restrictions imposed by society. The behavioral approach American
psychologist John Watson studied only what he could observe directly,
but not unobservable mental events. By focusing on observable actions
alone, said Watson, psychologists would not have to rely on people's
possibly distorted reports about mental processes and could begin to
understand behavior whether it occurs in adults, children, the mentally
ill, or animals. Watson’s views gave birth to the behavioral approach to psychology. According to this approach, the pattern of rewards and punishments that each person has experienced determines most behaviors and ways of thinking The humanistic approach A fundamental assumption of the humanistic approach is
that people control themselves. Furthermore, according to this
approach, each person has an innate tendency to grow toward his or her
own potential, although the environment (including other people) may
block this growth or stimulate it. According
to the humanistic perspective, behavior is determined primarily by each
person's capacity to choose how to think and act. These choices are
dictated by each individual's unique perception of the world. If you
perceive the world as a supportive, friendly place, you are likely to
feel happy. The cognitive approach In the last fifteen years the cognitive approach - has become particularly influential. The cognitive approach
emphasizes the importance of thoughts and other mental processes. This
perspective focuses directly on mental processes - that is, on how the
brain takes in information, uses its functions of perception, memory,
thought, judgment, decision making and the like to process that
information and generates integrated patterns of behavior. The
question of which of these approaches is the "right" one can never be
answered simply because "tightness" or "wrongness" is not at issue.
Each approach to psychology emphasizes a particular set of factors that
tells part of the story of behavior and mental processes. The goals of researchThe basic goals of research are description, prediction, control, and explanation. Description Accordingly
to Bernstein D.A.”… in order to answer any research question, the
psychologist must first describe the phenomenon of interest, gather
detailed information about case, measure and summarize data before
aiming for more ambitious goals . Such descriptive data are usually
collected through surveys, case studies, and observations”. Prediction Noticing interesting patterns and apparent relationships, psychologist might aim for a more ambitious research goal: prediction.. When a prediction is stated as a specific, testable proposition about a phenomenon, it is called a hypothesis.
To test his hypothesis, psychologist would gather additional data,
looking not only for evidence that supports the hypothesis but also for
evidence that refutes it. In research aimed at prediction, one tests hypotheses by analyzing descriptive data in order to detect relationships between variable. Variables are specific factors or characteristics that can vary in some way. The relationships detected in prediction-oriented research usually appear as correlations. Correlation means the degree to which one variable is related to another. Control A
scientist trying to describe or predict data , might find it difficult
to choose among a number of hypotheses if he will use only
correlational methods. The psychologist might aim for another goal:
control. A scientist would try to establish a situation in which
factors that might interfere with an understanding of the cause-effect
relationship are eliminated. The procedure when we can manipulate one variable and observe its effect on another variable, we call the result controlled research. Controlled research involves experimental methods, controlled experiments can also be conducted in the "real world" . Explanation Scientists
can begin to suggest-explanations after examining data from
descriptive, predictive, or controlled research (usually all three).
Explanations often include or lead to the formation of general rules
about certain categories of behavior or mental processes. These general
rules are organized into a theory,
which is an integrated set of principles that can be used to account
for, predict, and even control certain phenomena. Some explanations in
science are so well established that they become known as laws.
Research metodsSpecific methods used to conduct research include surveys, case studies, naturalistic observations, and experiments. Survey methods involve giving people questionnaires or special interviews designed
to obtain descriptions of their behavior, attitudes, beliefs, opinions,
and intentions. For example, surveys in psychological research have
helped clarify differences in the ways people from different social
classes discipline their children (lower-class families tend to be more
strict). Usually survey data lead psychologists to formulate
predictions and testable hypotheses and to test those hypotheses
through additional correlational and experimental research. A case study
is an intensive examination of some phenomenon in a particular
individual, group, or situation. Case studies are especially useful
when a phenomenon is very complex or relatively rare. The use of case
studies has a particularly long tradition in clinical psychology.
Freud’s development of psychoanalysis, for example, was based on case
studies of “neurotics” whose other physical symptoms disappeared when
they were hypnotized or asleep. Case studies have one major limitation,
however: cases are not necessarily representative samples. Sometimes the best way to gather descriptive data about a psychological phenomenon is to observe it
as it occurs in the natural environment. This is especially true when
other approaches are likely to be disruptive or misleading. Clinical
psychologists use naturalistic observation to gather information about
a person’s problematic behavior in preparation for changing it.
Similarly, industrial-organizational and engineering psychologists
observe how groups or equipment function before they suggest changes Experiments are arrangements in which the researcher manipulates or controls
one variable and then observes the effect of that manipulation on
another variable. The variable controlled by the experimenter is called
the independent variable. The variable to be observed is called the dependent variable because it is affected by or depends on the independent variable. The group that receives the experimental treatment is called the experimental group. The people who receive no treatment are called control group. The process of selecting subjects for any experiments is called sampling. In
order for an experiment’s results to reveal something about people in
general, the researcher chooses subjects who are representative of
people in general. When every member of the population has an equal
chance of being chosen for study, the individuals selected constitute a random sample. If not everyone in a population has an equal chance of being selected the sample is said to be a biased sample. Confounding variables
confuse or confound interpretation of an experiment’s results. Any
factor that might have affected the dependent variable along with or
instead of the independent variable, may be a confounding variable.
When confounding variables are present, the investigator cannot know
which variable was responsible for the results - the one that was
manipulated or the confound. Results
can also be confounded by the basic design of an experiment. When
medical and psychological treatments are evaluated, improvement
stemming solely from the subjects’ knowledge and perceptions of those
treatments is usually called the placebo effect. A placebo
is a treatment that contains no active ingredient but nevertheless
produces an effect because a person believes it will have that effect.
Patients may improve after they are given a new drug, not because the
drug contains an effective treatment for their illness, but because
they believe that the drug will help them. A fourth potential confound comes from experimenter bias,
the unintentional effect that experimenters may exert on results. To
prevent experimenter bias from confounding results, experimenters use a double-blind design,
in which both the subjects and those giving the treatments are unaware
of, or “blind” to, who is receiving a placebo. Only the director of the
study - a person with no direct contact with the subjects - knows who
is in the experimental group and who is in the placebo group. Questions and tasks on the main topics. 1.What is the psychology science? 2.What are the main psychology topics ? 3.What psychological approaches are used in psychological studies? 4.Name the main theoretical approaches used in psychology. 5.What are the main goals of psychological research? 6.What research methods are used by the psychologists ? Theme 2. Sensory System. From Sensation to Perception.The main topics. 1.Sensory system, problem of coding, representing stimuli in the brain. 2.Touch and temperature. 3.Pain 4.Perception, its futures, organization, constancy. 5.Depth perception. 6 Perceptual illusions. A sense is
a system that translates data from outside the nervous system into
neural activity, giving the nervous system, especially the brain,
information about the world. For example, vision is the system through
which the eyes convert light into neural activity that tells the brain
something about the source of the light (for example, that it is
bright) or about objects from which it is reflected (for example, that
a round, red object is out there). These messages from the senses are
called sensations
and comprise the raw information that affects many kinds of behavior
and mental processes . Psychologists have distinguished between
sensation - the initial message from the senses - and perception,
or the way the message is interpreted and given meaning in terms of
previous experiences. Thus, you do not actually "sense" a cat lying on
the sofa; you see shapes and colors - visual sensations. But, because
of your previous knowledge of the world, you interpret or perceive
these sensations as a cat. Steps in Sensation The first step in sensation involves accessory structures, which modify the stimulus. For example: the
lens of the eye is an accessory structure that changes incoming light
by focusing it; the outer part of the ear is an accessory structure
that collects sound. The second step in sensation is transduction - the
process of converting incoming energy into neural activity. As a radio
receives energy and transduces it into sounds, the ears receive sound
energy and transduce it into neural activity that people recognize as
voices, music and other auditory experiences. Transduction takes place
at structures called receptors,
cells that are specialized to detect certain forms of energy. Than
sensory nerves transfer the receptor’s activity to the brain. For all
the senses but smell, the information is taken first to the thalamus,
which relays it to the cerebral cortex. Each
nerve cell that carries sensory information responds to only a small
part of the incoming energy. This portion of the world that affects a
given neuron is its receptive field. The Problem of Coding Coding
is the translation of a stimulus's physical properties into a pattern
of neural activity that specifically identifies those physical
properties. If you want the brain to see the sundae, you should
probably stimulate its optic nerve (the nerve from the eye to the
brain) rather than its auditory nerve (the nerve from the ear to the
brain). This idea is based on the doctrine of specific nerve energies: stimulation of a particular sensory nerve provides codes for that one sense, no matter how the stimulation takes place. Representing Stimuli in the Brain Sensory
systems transfer information to the brain and they also organize that
information. This organized information is called a representation.
Accordingly to Bernstein D.A. “…in humans, representations in the
cerebral cortex of vision, hearing, and the skin senses share the
following features: 1. A primary area of sensory cortex receives information through the thalamus from each of these senses. 2. The representation of the sensory world in the cortex is contralateral
to the part of the world being sensed. Thus, for example, the left side
of the primary visual cortex "sees" the right side of the world, and
the right side of the somatosensory cortex "feels" the left side of the
body. This happens because nerve fibers from each side of the body
cross on their way to the thalamus. 3. The primary cortex contains a map or topographical representation of
each sense. This means that any two points that are next to each other
in the stimulus will be represented next to each other in the brain.
The proportions on the sensory map may be distorted, but the
relationships among the various points are maintained. 4.
The density of nerve fibers at any given part of a sense organ
determines the extent of its representation in the cortex. For example,
your fingertips, which have many receptors for touch, have a larger
area of cortex representing them than does the skin on your back. 5.
Each region of primary sensory cortex is divided into columns of cells
that have similar properties. For example, one column of cells in the
visual cortex might respond most to diagonal lines; another column
might respond most to edges. 6.
For each of the senses regions of cortex other than the primary areas
do more complex processing of sensory information. Called association cortex,
some of these areas contain representations of more than one sense;
others provide additional representation areas for a given sense.
Hearing, for example, is represented in several association areas”. Thus, sensory
systems convert some form of energy into neural activity. Often the
energy is first modified by accessory structures; then a sensory
receptor converts the energy to neural activity. The pattern of neural
activity codes physical properties of the energy. The codes are
modified as the information is transferred to the brain and processed
further. SOMATIC SENSES AND THE VESTIBULAR SYSTEM As we know, some senses are not located in a specific organ, such as the eye or the ear. These are the somatic senses, also called somatosensory systems,
which are spread throughout the body. The somatic senses include the
skin senses of touch, temperature, and pain, and kinesthesia, the sense
that tells the brain where the parts of the body are. It is not
strictly a somatosensory system, the vestibular system will also be
considered in this section because its function - telling the brain
about the position and movements of the head - is closely related to kinesthesia. Touch and Temperature Touch
is vitally important . A person without touch would have difficulty
surviving. Without a sense of touch, you could not even swallow food. The stimulus and receptors for touch
The energy detected and transduced into neural activity by the sense of
touch is a mechanical deformation of tissue, generally the skin,
frequently by stimulation of the hairs on the skin. Fingertip
touch is the main way we explore the textures of surfaces. It can be
extremely sensitive, as is evident not only in sensual caresses but
also in the speed with which blind people can read Braille. The mouth,
especially the lips, also has many touch receptors . For infants and
young children, who have not developed the ability to coordinate hand
movements, the sense of touch in the mouth is an important way of
learning about the world. Adaptation of touch receptors. Sensibilisation. The touch sense focuses changes and filters out excess information through adaptation - the process through which responsiveness to a constant stimulus decreases over time. A
touch nerve responds with a burst of firing when a stimulus is applied,
then quickly returns to baseline firing rates, even though the stimulus
may still be in contact with the skin. If the touch pressure increases,
the nerve again responds with an increase in firing rate, but then it
again slows down. A much smaller number of nerves adapts more slowly,
continuing to fire at an elevated rate as long as pressure is applied
to the skin. The increasing sensitivity after training receptors and as a result of its relations is called sensibilisation. Pain A
change in the intensity of the same kind of stimulation can create a
distinctly different sensation: pain. Pain provides you with
information about the impact of the world on your body; it can tell
you: "You have just crushed your left thumb with a hammer." Pain also
has an aversive emotional component. It is still unknown about how pain is created, but it appears that painful stimuli damage tissue and cause the release of bradykinin. Bradykinin fits into specialized receptors in pain nerves, causing them to fire. Pain signals are carried from the skin to the spinal cord by A-delta fibers (carry sharp pain), and (C fibers
carry several types of pain, including chronic, dull aches). These same
C fibers also respond to no painful touch, but with a different pattern
of firing. Both A-delta and C fibers carry the pain impulses into the
spinal cord, where they form synapses with neurons that carry the pain
signals to the thalamus and other parts of the brain. Modulation of pain: The gate theory The nervous system has several mechanisms for controlling the experience of pain. The gate theory explain how
the nervous system controls the amount of pain that reaches the brain .
It holds that there is a functional "gate" in the spinal cord that
either lets pain impulses travel upward to the brain or blocks their
progress. This gate can be closed by two mechanisms. First, impulse from skin
senses can come into the spinal cord at the same time the pain gets
there and can "take over" the pathways that the pain impulses would
have used. Thus, nonpainful and painful sensations coming into the
spinal cord in effect compete for pathways to the brain. That’s why
rubbing the skin around a wound reduces the pain you feel and
electrical stimulation of the skin around a painful spot relieves the
pain. Second,
the brain can close the gate by sending signals down the spinal cord.
These messages from the brain block pain signals when they synapse in
the spinal cord. Finally it is analgesia, the absence of the sensation of pain in the presence of a normally painful stimulus. Proprioception The
sensory systems receive information from the external world, such as
the light reflected off green grass or the feeling of cool water
washing over your feet. But as far as the brain is concerned, the rest
of the body is "out there" too, and we know about where we are and what
each part of our body is doing only because sensory systems provide
this information to the brain. These sensory systems are called proprioceptive ("received from one's own"). The sense that tells you where the parts of your body are with respect to each other is kinesthesia. You do not think much about kinesthetic information, but you definitely use it. Even
though, with your eyes closed, you can usually do a decent job of
touching two fingers together in front of you. To do this, you must
know where each finger is with respect to your body. You also depend on
kinesthetic information to guide all your movements. Otherwise, it
would be impossible to develop or improve any motor skill, from basic
walking to complex athletic movements Kinesthesia
also plays an important role in a person's sense of self. Normally,
kinesthetic information comes from both muscles and joints. Receptors
in muscle fibers send information to the brain about the stretching of
muscles, although their main role is to control muscle contraction .
The primary source of kinesthetic information comes from joint receptors.
These are nerve endings similar to those in the skin, but they are
located where two bones meet, and they respond to deflections of the
joint. When the position of the bones changes, joint receptors
transduce this mechanical energy into neural activity, providing
information about both the rate of change and the angle of the bones.
This coded information goes to the spinal cord and is sent from there
to the thalamus along with sensory information from the skin. It goes
to the somatosensory cortex and to the cerebellum , which is involved
in the coordination of movements. The vestibular sense
tells us about the position of the body in space and about its general
movements. It is often thought of as the sense of balance. We usually
become aware of the vestibular sense only when we overstimulate it and
become dizzy. Two vestibular sacs and three semicircular canals which
are part of the inner ear are the organs for the vestibular sense. The
vestibular sacs are filled with fluid and contain small crystals called
otoliths ("ear
stones") that rest on hair endings. Because gravity pulls the otoliths
toward the earth, they shift when the head tilts, stimulating the hair
endings and providing information to the brain about the position of
the head with respect to the earth. The semicircular canals
give information that is independent of the earth. They are
fluid-filled, arc-shaped tubes that are oriented in three different
planes. Tiny hairs extend into the fluid in the canals. Whenever the
head moves or changes its rate of movement in any direction, the fluid
in at least one of the canals moves, bending the hairs. This bending
stimulates neurons that travel with the auditory nerve, signaling to
the brain the amount and direction of head movement. The
vestibular system has neural connections to the cerebellum, to the part
of the autonomic nervous system that affects the digestive system, and
to the muscles of the eyes. The connections to the cerebellum help
coordinate bodily movements. The connections to the eye muscles create
vestibular-ocular reflexes. FROM SENSATION TO PERCEPTION: Perception is the psychological process through which sensations from the environment are transforming. Using knowledge and understanding of the world perception create our meaningful experiences. Some Features of Perception There are six features of perception. First, perception is generally knowledge based. Second, perception is often inferential.
People do not always have complete sensory information at hand, but the
perceptual system uses people's knowledge or make inferences about what
they may not be able to hear, see or feel. Third, perception is categorical; it allows people to place apparently different sensations in the same category based on some common features. Fourth, relational feature of perception. Fifth, perception is adaptive, allowing people to focus on the most important information for handling a particular situation. This
aspect of perception helps us to identify quickly stimuli associated
with food or other desirable goals, as well as those that are likely to
be dangerous. And finally, many perceptual processes operate automatically. Absolute Thresholds The
simplest perceptual categorization involves deciding whether a stimulus
is present. This process begins with and depends on the sensory
receptors and raw sensations. The minimum detectable amount of light, sound, pressure or other physical energy is called the absolute threshold. This
threshold can be amazingly low. Normal human vision, for example, can
detect the light equivalent to a single candle flame burning on a dark
night thirty miles away! An area that study the relationship between the physical energy of environmental stimuli and the conscious psychological experience those stimuli produce has a name psychophysics. There
is a typical experiment on the absolute threshold for vision. In a
laboratory the lights are turned out. After the subject's eyes have
adapted to the darkness, many brief flashes of light are presented one
at a time at varying intensities, from less than that of a candle
burning thirty miles away to levels considerably higher. Each time the
subject is asked if the stimulus was seen. The pattern of “ yes” or
“no” responses to the varying light intensities usually forms a curve. The exact
amount of energy corresponding to any particular person's absolute
threshold cannot actually be determined. Psychophysicists have
redefined the absolute threshold as the minimum amount of energy that can be detected 50 percent of the time. Principles of Perceptual Organization There are two basic principles of perceptual organization - figure and ground perception and grouping. Figure and ground.
Looking at a complex visual scene or listening to a noisy environment,
our perceptual apparatus automatically picks out certain objects or
sounds to be figures (that is, the features to be emphasized) and relegates others to be ground (that is, background). Grouping
Certain inherent features of stimuli lead people to group them
together, more or less automatically, into coherent objects or sounds. Certain parts of the perceptual world become figure and others become background. In
the beginning of twentieth century, a group of German psychologists
argued that people perceive sights and sounds as organized wholes.
These wholes, they said, are different from and more than just the sum
of the individual sensations. Because the German word meaning roughly
"whole figure" is Gestalt, these researchers became known as Gestalt psychologists. They proposed six principles that lead the perceptual system to connect sensations together in particular ways, organizing it in patterns. These principles are: 1. Proximity The closer objects are to one another, the more likely they are to be perceived as belonging together. 2. Similarity
Similar elements are perceived to be part of a group. People wearing
the same school colors at a stadium will be perceived as belonging
together even if they are not seated close together. 3. Continuity Sensations that appear to create a continuous form are perceived as belonging together. 4. Closure People tend to fill in missing contours to form a complete object. 5. Orientation
When basic features of stimuli have the same orientation (such as
horizontal, vertical, or at an angle), people tend to group those
stimuli together. Thus, you group the vertical lines of a grove of
standing trees together and see those trees separately from their
fallen neighbors in the undergrowth. 6. Simplicity People tend to group stimulus features in a way that provides the simplest interpretation of the world . Perceptual Constancy Perceptual constancy
means that the perception of objects as constant in size, shape, color,
and other properties despite changes in their retinal image. Without
this aspect of perception, the world would be an Alice-in-Wonderland
kind of place in which objects continuously changed their properties.
Perceptual constancy includes : size constancy, shape constancy, and
brightness constancy. Depth Perception: Experiencing the Third Dimension Perception of distance, or depth perception,
allows people to experience the world in three-dimensional depth, not
as a two-dimensional movie. There are two reasons why we perceive the
world in three-dimensional depth. The first involves a wide variety of cues provided by the environment. The second is a set of properties of the visual system itself. The cues provided by the environment includes: the principle of relative size (objects producing larger images on the retina are perceived as closer than those producing smaller ones) , interposition ( closer objects block one's view of things farther away). Greater distances usually produce less clarity. Reduced clarity
is interpreted as a cue for greater distance. The effect of clarity on
perceived distance explains why a mountain viewed on a hazy day appears
to loom larger than the same mountain on a clear day. Two another stimulus cues for depth come from gradients, which are continuous changes across the visual field. A textural gradient is a graduated change in the texture, or "grain," of the visual field. The second gradient cue is the movement gradient,
which is the graduated difference in the apparent movement of objects.
Faster relative movement across the visual field indicates less
distance. For example, you are riding
in a car in an open area, look out the side window at an object of
intermediate distance (for example, a house). The telephone poles and
other objects closest to you will appear to fly across your visual
field at a rapid rate; in contrast, distant trees may seem motionless
or even appear to move along with you. This difference in relative
movement provides cues to the difference in distance. Cues based on properties of the visual system Each human eye is located at a slightly different spot on the head and each eye receives a slightly different view of the world. The difference between the two retinal images of an object is called binocular disparity
and is responsible for creating the experience of a solid,
three-dimensional object. For any particular object, this disparity
decreases with increasing distance. With both eyes open, the brain
combines the two images, processes information about the amount of
disparity and the distance, and generates the impression of a single
object having its correct depth, as well as height and width. Binocular
disparity is one of the strongest cues of depth perception. The final depth cue based on the anatomy of the eye. It is related to fact that the lens of the eyeball changes shape or accommodates.
Muscles surrounding the lens must either tighten to make the lens more
curved for focusing on close objects or relax to flatten the lens for
focusing on more distant objects. Information about the muscle’s
activity is relayed to the brain, and this accommodation cue helps
create the perception of distance. Perceptual Illusions The
perceptual attributes we have described constantly and automatically
convey precise information about the features of a multitude of objects
and surfaces. But this information can distorts. Distorted perceptions
can come about through sleep, hypnosis, drugs, and other circumstances;
here we are concerned with those distortions of reality known as perceptual illusions. The best-known and most studied perceptual illusion is the Miiller-Lyer
illusion. Of the two arrow shafts ( in the Figure 1 a ), the one on the
left seems shorter, despite the fact that the two are of equal length.
The convergence of the arrowheads on each side of the shaft on the left
makes the shaft appear to be the closest part of the scene (like the
outside corner of the house in Figure 1 b), whereas the divergence of
the arrowheads on the right makes that shaft seem to be toward the
back. Attractive
and simple as the depth perception theory of the Muller-Lyer illusion
may seem, it cannot account for some phenomena. A striking example is
shown in Figure 1 c. In this figure there are no converging lines to
suggest
Fig. 1. Variations on the Muller-Lyer illusion. Source: J.M. Darley et all Psychology, 1981. distance,
and the figure does not give a feeling of three-dimensionality; yet it
does create a misjudgment of distance like that in the Muller-Lyer
illusion. Object is based on the
"frame" of which it is a part. When the frame is perceived as larger,
as it is in the right side of Figure 1, c, so is the line segment
included within it (Rock, 1977 ). In
short , since perception is based on many principles, it seems
reasonable that illusions could reflect the violation of more than one
of them. Alterations of perception
may also be created not by cues provided by the environment, but by the
same factors that create response bias in detecting stimuli:
motivation, experience, bias, and expectancy. Questions and tasks on the main topics. 1.What are the processes of sensation and perception? 2.What are the main features of perception? 3.Name the main principles of perceptual organization and characterize them. 4.How do we gain experience the third dimension? Theme 3. AttentionThe Main Topics. 1.Selective attention 2.Focused and divided attention. Attention
is the process of directing and focusing certain psychological
resources, usually by voluntary control, to enhance information
processing, performance, and mental experience. For
example, in order to read this page, you focused a psychological
resource when you shifted your attention from the television, the
newspaper or whatever else you were
paying attention to earlier. And you will do it again, should you shift
from reading to listening to a nearby conversation (even though your
eyes may remain fixed on the book). Attention is selective, it focus on some stimuli while ignoring others. Stimuli
that have certain properties tend to attract attention. Characteristics
of stimuli that may attract attention include large size, high
intensity, contrast, and novelty. Focused and Divided Attention. Look
at the list of words in Figure 2.. Color the words in different colors
which will distinguish from the real meaning of the word ( blue in
green color ). Now read the list and say aloud, as fast as you can, the
color of the ink in which each word is printed. Blue Green Green orange Purple orange Red red Grey blue Fig. 2 This simple task illustrates two facts about attention. First - it
is all too easy to lose the focus of attention on one particular
stimulus or stimulus aspect when another aspect is also attention
getting. In this case, two competing stimulus aspects are color and the
meaning of a single word. Second - it may be very easy to divide
attention between two stimuli or aspects of stimuli, especially if they
are physically close or similar. Thus, the difficulty of the task lies
in the fact that you are perceiving both the meaning of the word and
its color at the same time, but must try to ignore one stimulus aspect.
Whereas attention may be divided between two aspects of a single
stimulus, it is not so easy to divide attention between very different
stimuli or between different tasks. This limitation can be
inconvenient, as when you try to watch television and have a
conversation at the same time. The
ability to divide attention between visual events is also limited. In
one experiment, for example, people watched a screen on which two video
games were superimposed. When they were told to focus attention on the
stimuli in one of the games, they became totally unaware of events in
the other game .The beam of attention was not wide enough to capture
two visual stories taking place at the same location. The
ability to divide attention is not entirely fixed. It depends in part
on how much people practice doing it, what kind of simultaneous stimuli
are present, and the amount of stress involved. Practice
People who are experienced at dividing their attention do better at it
than novices. Experience helps because extensive practice allows a
person to process and act on perceptual information so automatically
that the practiced task requires little attention.. Obviously, it is
easier to divide attention between two sets of stimuli when one of them
no longer requires much attention in order to be perceived and
processed. Nature of the stimuli
In general, the closer together two stimuli are, the more easily they
can be perceived at the same time. Dividing attention is also easier
when the stimuli do not compete for attention through the same sensory
system, because the human brain appears to have more than one pool of attentional
resources and more than one spotlight of attention. Having different
attentional resources is a little like having an extra person available
to help out when there is more than one job to do at the same time.
However, each spotlight of attention tends
to focus on a particular sensory channel. Thus, if two sets of stimuli
(say, a light and a sound) involve different senses, people can more
easily perceive them at the same time than if both are visual or
auditory and thus have to compete for the same resources. This is one reason why skilled secretaries can type and shadow efficiently at the same time: typing requires visual perception and movement of the fingers
and hands, whereas shadowing requires auditory perception and vocal
responses. Somewhat different attentional resources are used in each
task. Questions and tasks on the main topics 1.What problems are studied in psychophysics ? 2.Give the full description of attention? Theme 4. Memory.The main topics: 1.Preliminary distinctions. 2.Encoding, storage, retrieval. 3.Working and long-term memory. 4.Decay. Memory is the way we record the events of our lives and also the information and skills we glean from these events. This capacity is necessary for humans or any other animal. Without memory, there would be no experience,
no learning, no ability to build or hone skills, no recall of names or
recognition effaces, no reference to past days or hours or even
seconds. This feeling of personal identity is necessarily based upon a
continuity of memories that links our yesterdays to our todays. Studying Memory . In compliance with Gleitman H.
“… the first step is to realize that memory is not a single entity and
that there is no single set of memory processes. Instead, the term memory is a blanket label for a large number of processes that work together to create a bridge between our past and our present”. We
use our memories to connect a wide range of time intervals. Sometimes,
we need to remember something we learned just moments ago; in some
cases, we draw on knowledge gained months or even years earlier., on
other occasions we are asked to recall material that has never been out
of our thoughts: for example you hear a bit of news, continue to think
about it for a while, and then, without interruption, are asked to
report what you had heard. These different retention intervals are served by different memory systems. Information learned long ago is stored in long-term memory. This memory system allows materials to lie in memory for long periods of time. Other information is stored in working memory. This is the memory system that stores information we are working on right now. When we search our memories for particular fact, we are using episodic memory - a memory for a specific event. When we must remember how to combine words to form sentences we use our generic memory. Generic memory is our mental library - it holds our mental dictionary and is also the storehouse for all our commonsense knowledge. When searching for the answer to “What did you have for dinner last night?” we are dealing with explicit memory. Sometimes, though, we are influenced by the past without our realizing it at all. Implicit memory is the sort of memory without awareness. Thanks to this memory we regard sentences we have heard before. Encoding, Storage, Retrieval The act of remembering implies success at four aspects of the memory process. First is the acquisition.
In order to remember, one must have learned. For example, imagine
meeting someone at a party, being told his name, and moments later
realizing that you no longer know it! This experience is probably not
the result of ultra-rapid forgetting. Instead, it is likely to stem
from a failure in acquisition: You were exposed to the name but barely
paid attention to it and, as a result, never learned it in the first
place. Another memory process is encoding. The term encoding
refers to the form in which an item of information is to be placed in
memory. Thus, a physician learning about a new medication might focus
on its uses, without giving much thought to its side effects. Or she
might focus on the biochemical mechanisms through which the drug works,
without thinking about how a patient’s life might be improved by it.
Such differences in emphasis during encoding can have a profound effect
on how (or whether) this information will be remembered later. The next aspect of remembering is storage: To be remembered, the encoded experience must leave some record in the nervous system (the memory trace). The final phase is retrieval, the point at which we try to remember. One way to retrieve material is through recall.
This refers to our efforts to supply information from memory in
response to a specific cue or question. Trying to answer questions like
“What was the name of that medicine you learned about last year?” or
“Can you remember where you read about that new medicine?” all require
a different recall. A different way to retrieve information is through recognition.
In this kind of retrieval, we are presented with a name, fact, or
situation and asked if we’ve encountered it before. “Was the medicine
perhaps called ‘Coaxil’?” would be a question requiring recognition. Encoding, Stage theory of Memory H. Gleitman also wrote that “… the stage theory of memory asserts that there are several storage systems, each with different properties. Working
memory holds information for short intervals - that is, while we are
working with it. Long-term memory, in contrast, stores materials for
much longer, sometimes for as long as a lifetime”. The
long-term memory has enormous capacity : The average college student
remembers the meanings of 80,000 words, thousands of autobiographical
episodes, millions of facts, hundreds of skills, the taste of vanilla
and the smell of lemon. All of this and much more art stored in
long-term memory. The capacity of working memory is limited. This capacity has been measured by a memory span task
in which the individual hears a series of items and must repeat them in
order after just one presentation. If the items are randomly chosen
letters or digits or short words, adults can repeat seven items or so
without error. With longer series errors are likely. This has led to
the assertion that working memory’s capacity is seven items, give or
take one or two. The
stage theory asserts that the road to long-term memory necessarily
passes through working memory. Working memory can be regarded as a
loading platform, sitting at the entrance to the huge long-term storage. Working
memory has a limited capacity: It can handle only a small number of
packages at any one time. However, what these packages contain is, to a
large extent, up to us. We can squeeze more information into the same
number of memory units. Recoding into larger chunks As an example, when we try to call a series of digits that he heard only once: 136162536596481 he
treats this as a series of fifteen unrelated numbers, we will almost
surely fail. But if we recognize that the digits form a pattern,
specifically 1 36 16 25 36 59 64 81 our
task becomes much easier. We only have to remember the underlying
relationship, “the squares of the digits from 1 to 9,” and the fifteen
components of the series are easily recreated. In this task, the person repackages the material to be remembered, recoding the input into larger units that are often called chunks.
This is crucial because working memory’s capacity appears to be
measured in chunks, rather than in bits of information. In general,
working memory seems able to hold seven plus-or-minus two chunks. If
each chunk contains only a single figure, then working memory can hold
roughly seven figures. If each contains a couple of figures (16,64 and
so on), then working memory can hold fourteen figures (two figures per
chunk) or seven chunks. The more information we jam into each chunk,
the more information can be stored. Much of the receding of memory items, or chunking, happens quite automatically .
According to the storage theory when an item is repeated over and over
again, it can be held in working memory, and this increases the
probability that the item will be transferred to long-term storage. But
it is not exactly so. The
entering long-term memory is not this automatic and depends on more
than the mere passage of time. Evidence comes from studies of maintenance rehearsal,
a strategy that keeps information in working memory but with little
long-term effect. As an everyday example, consider what happens when
you look up a telephone number. You need to retain the number long
enough to complete your call, but you have no need to memorize the
number for later use. In this circumstance, you are likely to employ
maintenance rehearsal: You repeat the number to yourself while you
dial. But what happens if the line is busy? A moment later, you try to
dial the number again, but realize you’ve already forgotten it.
Maintenance rehearsal kept the number in working memory long enough for
you to dial it the first time but failed to establish it in long-term
memory. As a result, the number is forgotten after just a few seconds. Mnemonics The development of techniques for improving memory processes are called mnemonics (or mnemonic devices). All mnemonics are build on the same base: We remember well what we organized well. Mnemonics through verbal organization
It is easier to remember verbal material if it is organized. Poetry,
with word sequences that maintain a fixed rhythm or rhyme, provides one
way to achieve this organization, and this fact has been exploited by
many cultures at many times. And in modern times verse is still used as an effective mnemonic (“Thirty days hath September April, June, and November”). Mnemonics based on visual imagery Some of the most effective mnemonics technique is the method of locus,
which requires the learner to visualize each of the items she wants to
remember in a different spatial location (locus). In recall, each
location is mentally inspected and the item that was placed there in
imagination is retrieved. Images are another way of forming chunks in memory, that is why it help. By creating a mental image, two unrelated items are joined and
that they form a new pattern . When part of the chunk (the imagined
locus) is presented the entire chunk is retrieved, yielding the part
required for recall. During
study and learning , we transfer new information from working memory
into our long-term store of knowledge. Successful encoding is not
enough. It is important be able to retrieve the information when we
need it; otherwise, what we’ve learned will be useless to us. The potential
difficulty of retrieval is obvious to anyone who has ever “blocked” on
a familiar name. We may know the word or name (have encoded and stored
it) but be unable to retrieve it when trying to introduce an old friend
to a new one. It is because the memory trace is inaccessible. Access to the trace can be restored by an appropriate retrieval cue, a stimulus that opens the path to the memory. Often
retrieval seems effortless: You are asked your middle name and
instantly respond. Sometimes, though, retrieval is more difficult,
requiring effort and a deliberate search for retrieval cues: You walk
out of the shopping mall and can’t remember where you parked your car.
But then you recollect that your first stop was at the drugstore, and
this seems to trigger the memory of squeezing the car into a narrow
space in the lot near the store. Mnemonics based on associating process In other
cases, retrieval initially seems impossible, as though the target
information was truly lost. But then some cue is presented and suddenly
the memory returns. A return to your home town, for example, after a
long absence, may unleash a flood of recollection, as the sights and
sounds of the place effectively trigger the relevant memories. A word,
a smell, a visit from a school friend not seen for years -any of these
may summon memories we thought were utterly lost. When Memory Fails. Memory
failures have many causes. Some arise from faulty encoding; others
arise at the moment of recall. In this section, we will discuss three
aspects of memory failure. One
concerns the passage of time: Ribot’s law of memory regression
formulates the finding that memory for resent events is lost before
memory for more remote events. That is why it is easier to remember the recent past than it is to remember events from long ago (Sims A, 1988 ). A second concerns memory
error-cases in which events are misremembered, so that the past as
recalled differs from the past as it actually unfolded. The third topic
concerns memory failure of a more extreme sort, as we consider what
happens to memory in certain kinds of brain damage. It is true that yesterday’s lesson is better remembered than last week’s, and last week’s better than last year’s. The longer time between learning and retrieval - that is, the longer the retention interval - the greater the chance of forgetting. The theory holds that memory traces simply decay as
time passes, like mountains that are eroded by wind and water. The
erosion of memories is presumably caused by normal metabolic processes
that wear down memory traces until they fade and finally disintegrate. In compliance with Crowder R.G.(1985) –“… memory is vulnerable to some sort of interference, with the newly arriving information interfering with the previously learned material. It seems that the forgotten material is neither damaged nor erased; it is simply misplaced in our memory. For
example - someone who buys a newspaper each day and then stores them in
a large pile in the basement. Each newspaper is easy to find when it is
still sitting on the breakfast table; it can still be located without
difficulty when it is on top of the basement stack. After some days,
though, finding the newspaper becomes difficult. It is somewhere in the
pile, but may not come into view without a great deal of searching.
And, of course, the pile grows higher and higher every day; hence,
interference will increase as the retention interval grows longer”. Among the different memory phenomena , the special interest concerns repressed memories.
Repression has been most discussed in connection with the recovery of
traumatic childhood men often memories involving sexual abuse. In these
cases, people often report that traumatic memories were pushed out of
consciousness - that is, repressed many years, sometimes for as long as
two or three decades. The memories than surface much later, often while
the person is being treated by a therapist for problem not obviously
connected to the alleged childhood events (Holmes, 1990). Disordered Memories Anterograde Amnesia. Certain
lesions in the temporal cortex (specifically, in the hippocampus and
nearby subcortical regions) produce a memory disorder called anterograde amnesia (anterograde means “in a forward direction”). Patients with this disorder often have little trouble remembering events after the
injury; their difficulty, instead, is in learning anything new. This
kind of amnesia can occur as a result of various brain lesions.
Anterograde amnesia is one of the symptoms of Alzheimer’s disease,
tragic side effect of neurosurgery undertaken to treat severe epilepsy
(Corkin,1984 ) . Retrograde Amnesia. An another set of deficits occurs in retrograde amnesia (retrograde
means “ in a backward direction”). The patient suffers a loss of memory
to period prior to the brain injury. A brief period of retrograde
amnesia always follows electroconvulsive therapy, a one kind of
treatment for severe depression or mania that involves brief electric
shocks applied to the head. Patients receiving this therapy have no
memories of their treatments or the events directly preceding. Longer
periods of retrograde amnesia, lasting weeks or even years, can result
from brain tumors, diseases or strokes. And in many cases, retrograde
effects accompany anterograde amnesia. Questions and tasks on the main topics. 1.Tell about the stage theory of memory. 2.What is the mechanism of working memory and that of long-term memory? 3.How can a great deal of information in working memory be held ? 4.Describe the difference between explicit memory and implicit memory. 5. What kinds of amnesia do you know ? Theme 5. Thought and Knowledge The main topics. 1.Mental representations. 2.Mental images. 3.Spatial thinking. 4.Knowledge and memory. 5.Solving problems, reasoning and decision making. In compliance with Gleitman H. “Many of the components of our knowledge can be regarded as mental representations of the world and of our experiences in it. These representations are the main elements of thought. Psychologists,
philosophers, and computer scientists have found it convenient to
distinguish between two broad classes of representations, the analogical and the symbolic.
Analogical representations capture some of the actual characteristics
of (and are thus analogous to) what they represent. In contrast,
symbolic representations create no such relationship to the item they
stand for. As we will see, human thought uses both kinds of
representations. ” Consider a picture of a mouse (Fig.2.). The picture ways
quite different from the real animal; the real picture consists of
marks on paper, whereas the actual mouse is flesh and blood. The
picture represents
a mouse rather than actually being one. The picture has many
similarities to the creature it represents, so that, in general, the
picture looks like
a mouse: The mouse's eyes are side by side in reality, and they're also
side by side in the picture; the mouse s ears and tail are at opposite
ends of the creature, and they're at opposite ends of the Fig. 2. picture. It is properties like these that make the picture an analogical representation. In contrast, the word mouse it is an abstract representation, and the relation between the five letters m-o-u-s-e and the little animal that they represent is entirely arbitrary. The
same situation holds for mental representations. Some of our mental
representations are images that reflect more or less directly many of
the attributes of the objects or events they represent. Other mental
representations are more abstract, much as words in a language. Mental Images. Some of our knowledge is based on analogical representations called mental images.
We seem to inspect these images with "our mind's eye," and read
information from these images much as we would read information off of
a picture. Similar claims have been made for other senses - including
hearing with the "mind's ear," or feeling with the "mind's fingers."
But far more is known about visual imagery than about imagery in these other modalities, and so our focus will be on visual images. Spatial Thinking Spatial thinking is closely
related to mental imagery , it is the kind that we use when we want to
determine a shortcut between two locations or when we mentally try to
rearrange the furniture in the living room. Most people have a general
conception of the layout of their environment. Accordingly to Jonides
and Baum (1978) , part of this knowledge is based on mental maps that
have pictorial qualities. For example, students were asked to estimate
the distances between various locations on their university campus - between
their dormitory and the main building, or between the student union and
the library. They were quite accurate in their estimates, but more
important was the time it took to provide these estimates. The longer
the distance, the longer the estimation time. It was as if the students
measured distances with mental ruler on a mental map, much as one might
measure the length of a wall with a small ruler. Other
kinds of spatial thinking involve processes that are symbolic , not
analogical. In one study research participants were asked to indicate
relative locations of Moscow and Tel-Aviv. The participants judged
Moscow to be west of Tel-Aviv, although it is actually father east.
Similarly, they judged Helsinki to be father north than St. Petersburg.
These results suggest that they weren’t biasing there answers on mental
maps at all. Instead, they seemed to be reasoning in this fashion:
Finland is north of Russia. Helsinki is in Finland. St. Petersburg is
in Russia. Therefore Helsinki is north of St. Petersburg. The knowledge being used in our examples is clearly symbolic, not pictorial. These symbolic formulations can lead to error. Accordingly to Gleitman H. “…the term concept describes a class or category that includes some number of individuals or subtypes. An example is dog, which includes poodle, livable, dachshund, and Alsatian. Other concepts designate qualities or dimensions. Examples are length and age. Still other concepts are relational, such as taller than. Notice that relational concepts don't apply to any one item in isolation. One can't be taller than except in relation to something else to which one's height is being compared.” In thinking, we combine concepts in various and sometimes complex ways. Such combination is association - a sense of "this goes with that”. Concepts are what we generally think about. Relationships among concepts, take the form of propositions. These are statements that relate a subject (the item about which the statement is being made) and a predicate
(what is being asserted about the subject). Propositions can be true or
false. For example, "Tom loves to play the football." "Mary plays
soccer," and "Squirrels eat burritos" are all propositions. But just
the words "Mary" is not propositions “plays soccer"- also ; the first is a subject without a predicate; the second is a predicate without a subject. Knowledge and Memory. When
we think, we often form new concepts and formulate new propositions.
But many concepts and propositions are already stored in memory, where
they constitute our accumulated knowledge, the "database" that sustains
and informs our thoughts. Such database is used generic memory,
which is memory for items of knowledge independent of the particular
occasion on which one acquired that knowledge. For example, we remember
that Paris is the capital of France, that three is the square root of
nine, and that sugar is an ingredient of most cookies. For
each person, generic memory contains an extraordinary wealth of know
edge, including the meanings of words and symbols, countless facts
about the world, what objects look like, and various general
principles, schemas, and scripts. Within this huge archive, one of the
important components is semantic memory,
which concerns the meanings of words and concepts. Our entire
vocabulary is in this store: every word, together with its
pronunciation, all of its meanings, its relations to objects in the
real world, and the way it is put together with other words to make
phrases and sentences. Several investigators have proposed network models of
generic memory. In the models, words and concepts are linked through a
complex system of relationships, so that it is possible to trace a path
through these relationships from or concept to other related concepts.
Within these networks, words or concepts are represented by nodes, while the associations between the concepts are indicate by associative links or associative connections. One
hypothesis, proposed early on, was that the network has a hierarchic
structure. But the relation between items of information in semantic
memory is more complex than the hierarchical model indicates . Difficulties with the hierarchical model led to the formulation of several alternatives, one of which is the spreading activation model.
In this model, concepts are still represented by nodes, with
associative links connecting one node to the next. However, this model
allows these links to represent many different kinds of relationships,
including relationships based on hierarchical position (as in canary-bird) or based on similarity of meaning (apple-orange), or on well-learned associations (peanut butter-jelly). The Process of Thinking: Solving Problems As Newell A. and Simon H.A. (1972) had written “… problem solving is not merely goal directed, it is also hierarchical: The effort to solve one problem often creates subproblems, so that one needs to reach certain subgoals
on the way toward achieving the main goal. And here, too, means-end
analysis is helpful: "I want to get to the store. What's the difference
between my current state and my goal? One of distance. What changes
distance? My automobile. My automobile won't work. What is needed to
make it work? A new battery...." In this case, the initial problem
(getting to the store) is replaced by a series of subproblems (e.g.,
getting the car to work). Or, the larger problem can be replaced with a
simpler and more familiar routine ( dressing, preparing cards or cash, locking the door ). By solving these, one at a time, the larger problem gets dealt with” So the routine is executed without much thought. In other words it becomes automatic and so is performed with minimal attention. In some circumstances this automaticity can create its own problems. A striking example of this is known as the Stroop effect,
named after its discoverer. To demonstrate this effect, research
participants are asked to name the colors in which groups of letters
are printed. If the letters are random sequences {fwis, sgbr) or irrelevant words (chair, tape), this task is rather easy. If, however, the letters form color names (yellow, red), the task becomes much harder. Thus, a participant might see red printed in green ink, blue
in brown ink, and so on. His task, of course, is simply to name the ink
color, and so he should say "green, brown," etc. But in this setting,
the participant can't help reading the words, and this produces a
strong competing response: He is likely to respond very slowly, because
while trying to name the ink colors, he is fighting the tendency to
read the words themselves aloud. Sometimes the solution involves a radical restructuring
by means of which a misleading set is overcome. Such restructurings may
be an important feature of much creative thinking. Some problems
initially seem quite difficult and the problem solver discovers an
alternative way to conceptualize the problem, breaking the mental set
that inhibited her, and soon after, comes up with the answer. Mental set - means that sometime we are fixed on one approach to task and correspondingly unable to think of the task in any other way. This restructuring
of a problem may be quite sudden, experienced as a flash of insight,
with an accompanying exclamation of "Aha!" Accounts by prominent
writers, composers, and scientists suggest that restructuring often
occurs after a period of incubation.
The idea here is that the thinker believes she has set the problem
aside but is actually continuing to think about it unconsciously.
Restructuring may also play a role in humor, which often occurs when an
unexpected cognitive organization turns out to make sense after all. Reasoning and Decision Making The goals that constitute the problem can vary widely .The further form of problem solving is of special interest. This is reasoning, in which the goal is to determine what conclusions can be drawn from certain premises. In compliance with Gleitman H. “ …in deductive reasoning, the reasoner tries to determine whether certain conclusions can be drawn - that is, deduced—from a set of initial assertions or premises.
According to logicians, the validity of the deduction depends on a
small number of rules, framed in terms of certain logical
relationships, such as and, or, not, and the like. But do humans follow these rules?” An example of deduction involves the analysis of syllogisms.
Each syllogism contains two premises and a conclusion, and the question
is whether the conclusion follows logically from the premises. Two
examples of such syllogisms (one valid, one invalid) are: All A are B. All B are C.___________ Therefore, all A are C. (valid) All A are B. Some B are C. Therefore, all A are C. (invalid ) In
deductive reasoning, we reason from the general to the particular. We
start with a general rule ("All people are mortal") and ask how it
applies to a particular case ("Pat Smith is a person"). But much of the
reasoning we engage in is inductive,
in which this process is reversed. Here we reason from the particular
to the general. We consider a number of different instances and try to
determine - that is, induce -what general rule covers them all. Induction and deduction both allow us to form new judgments and to form new beliefs. Questions and tasks on main topics. 1.Name the main classes of representations. 2.Give the example of analogical representation in thinking? 3. What are the elements of symbolic thoughts? Where many of these are stored? 4.What is the procedure of problem solving? 5.What is the way of reasoning? Theme 6. Intelligence. Its Nature and Measurement.The main topics: 1. What is intelligence? 2. Measuring Intelligence 3 The Causes of Retardation 4. Strategies and Intellectual Functioning 5. The Cultural Context of Intelligence The first question we are interested in - is.” What is intelligence?”. Our vocabularies are filled with words that describe different levels and types of intellectual functioning—smart, bright, and clever; dull, slow, and dim-witted. But it is difficult to specify exactly what these terms mean, and attempts at specification often lead to disagreements. Even psychologists disagree on exactly how intelligence should be defined. Some
researchers pay there attention to the capacity for abstract thinking.
Others focus on the ability to acquire new abilities or new knowledge.
Anothers highlight the ability to adapt to new situations. And there
are no single definition of intelligence that has been accepted by all.
Measuring Intelligence In
1904, in French minister of public instruction appointed a committee
with the task of identifying children who were performing badly in
school . Alfred Binet (1857—1911) suggested a project , pragmatic in its goals and quite optimistic in its tone. With
his collaborator, Theophile Simon, Binet believed that intelligence was
a general attribute, existing itself in many different spheres of
cognitive functioning. They construct a test that included many
subtasks varying in both content and difficulty: copying a drawing,
repeating a string of digits, understanding a story, and so on. Their
idea was that a person might do well on one or two of these tasks just
by luck or by virtue of some specific prior experience. A truly
intelligent person would be able to perform well on virtually any task
and certainly on all of the tasks in this array. And intelligence could
be measured by a composite score assessing how an individual did on all
the tasks in this set. The diversity of the tasks would ensure that the
test was not measuring some specialized talent but was instead a
measure of ability in general. Binet also believed that intelligence grew as the child grew, and this provided the basis for the test's scoring system. Alfred Binet was primarily interested in assessing children. His tests measured mental age, or MA. The standing of a child relative to her age mates was determined by comparing her MA with her chronological age, or CA, To determine the child's intelligence quotient, or IQ, MA is divided by CA and multiplied by 100. Thus, IQ=MA/CAX100. The
Binet test was originally meant for children, but demand soon arose for
the assessment of adults' intelligence. This led to the development of
a test standardized on an adult population - the Wechsler Adult
Intelligence Scale, or WAIS. Different intelligence tests have been developed for various goals: to test children, to test adults; to assess mental retardation. The Causes of Retardation What
causes retardation? Retardation can be traced to a specific genetic
disorder, as, for example, in Down's syndrome or a pattern known as
fragile-X syndrome (so-called because it involves damage to the X
chromosome). Retardation arises
because of a problem that affected the developing fetus - for example,
alcohol in the mother's bloodstream or certain diseases during
pregnancy, such as rubella. Retardation is the result of problems
related to birth itself, including premature birth or temporary oxygen
deprivation to the fetus. In other cases it arises from conditions
subsequent to birth, such as meningitis or head injury. This is a
diverse set of factors, and, in fact, some have estimated that there
are over two hundred causes of mental retardation, each with a specific
organic basis. All such cases lead to identifiable problems in the
nervous system; they also tend to have other symptoms associated with
them, and these symptoms play an important role in the diagnosis of
individual cases. Table
( 1, p.47 ) presents a description of the general level of intellectual
functioning at various ages in each of these four categories. Also the
table shows that mentally retarded persons do not have to be excluded
from useful participation in society. What is Intelligence? To
determine whether intelligence is one unitary ability or is composed of
several unrelated abilities, investigators have looked at the
correlations among different subtests. In compliance with Gleitman H. ”…factor analysis
of these correlations allows us to extract a measurement of the common
factor that seems to be shared among all of these tasks; The author of
this technique was Charles Spearman. Spearman argued that this factor is best described as general intelligence, or g.
He proposed that g is a mental attribute called upon for any
intellectual task, and so individuals with a lot of g have an advantage
in every intellectual endeavor. If g is in short supply, the individual will do poorly on a wide range of tasks”. Differences
in the cognitive processes that underlie remembering, problem solving,
and thinking are seen as individual differences in intellectual
performance One line of inquiry tries to relate Spearman's g to differences in reaction time.
Another approach focuses on a sub factor, such as verbal intelligence,
and relates it to simple cognitive operations, such as memory look-up
times. A third approach emphasizes the more complex cognitive components of
the tasks posed by standard intelligence tests, as exemplified in
studies of analogical reasoning. A fourth line of inquiry investigates
the role of working memory and attention. . In solving an analogy
problem, for example, one must keep track of the various terms and of
their attributes. One must also remember which relationships have
already been examined (and found unsatisfactory), so that one doesn't
keep examining the same relationships over and over. All of this
requires memory storage, as well as attention, as one focuses on
different aspects of the problem and develops new interpretations of it. This
leads to an obvious proposal: Individuals with ample working memory and
attention should perform better on analogy tests and also on a wide
range of other tasks. Individuals without these capacities will perform
worse. To test this suggestion, researchers have developed active-span tasks, procedures designed to assess an individual's ability to store and manipulate different pieces of information simultaneously. Strategies and Intellectual Functioning A
normal adult can master memory tasks that are generally beyond the
reach of a six-year-old, and an important reason for this lies in the
strategies the adult uses. Suppose she is asked to memorize unrelated
materials, such as the words tulip plumber tiger sweater lily tailor daisy raincoat monkey butcher zebra jacket. An
adult will do her best to rehearse this list of items and probably will
also try to organize the list in some way. For example, she might try
rhythmic grouping by, say, repeating the items in threes: "tulip,
plumber, tiger . . . sweater, lily, tailor, . . . daisy, raincoat,
monkey. ..." Or she might try to organize the list of items into
categories, thinking first about the flowers, then the occupations,
then the animals. Any of these organizational devices will help her in
later tests of recall. A six-year-old, in contrast, is unlikely to have
such organizational tricks in her repertoire and so will be less
successful at such intellectual tasks. The
use of such strategies also accounts for some of the intellectual
differences among adults, with the best evidence coming from extreme
differences in ability, such as the differences between adults who
function normally and retarded individuals. The evidence suggests, for
example, that retarded examinees attack memory tasks with little or no
resort to organization. They are less likely to rehearse, to group
items in a list, or to show recall clustering by semantic categories .
Strategy use also provides part of the reason why the elderly often
have trouble in remembering - they fail to use strategies when they
first encounter the to-be-remembered materials and so are at a
disadvantage later on, when the time comes to remember this material
.The same is true for individuals who are depressed; they engage poorly
with the to-be-remembered materials during learning, and so have
difficulty retrieving them later on. What is Intelligence? Beyond IQ. Howard Gardner's concept of multiple intelligences
is a different attempt to expand the notion of intelligence. He notes,
for example, that some individuals are exquisitely talented in music,
even though they seem quite ordinary in other respects. This suggests to Gardner that musical intelligence is separate and distinct from other forms of intelligence.
Similar considerations led him to argue for the existence of six
specialized "intelligences": linguistic, logical-mathematical,
spatial, musical, bodily-kinesthetic and personal intelligence. Musical
ability includes skill in composition and in performance. By
bodily-kinesthetic intelligence Gardner refers to the ability to learn
and create complex motor patterns as in dancers and skilled athletes.
By personal intelligence he refers to the ability to understand oneself
and others. Another argument for Gardner's theory comes from the study of so-called savants (formerly, idiot savants). These are generally profoundly retarded persons who have
some single extraordinary talent. Some display unusual artistic talent
. Others are "calendar calculators," able to answer immediately (and
correctly!) if asked questions such as, "What day of the week was March
17 in the year 1683?" . Still others have unusual mechanical talents or
unusual musical skills, for example, effortlessly memorizing lengthy
and complex musical works. We
might raise a further concern about Gardner's theory: There is no
question that some individuals - whether savants or otherwise - have
special talents and that these talents are immensely impressive.
However, is it appropriate to think of these talents as forms of
intelligence? Or might we be better served by a distinction between
intelligence and talent? To put this differently, is being smart a
talent in the same sense that being able to play the violin is a
talent? The answers to these questions are far from clear, and this
makes Gardner's claims difficult to evaluate. Whatever
the ultimate verdict on Gardner's theory, there is no doubt that he has
performed a valuable service by drawing attention to a set of abilities
that is often ignored and certainly undervalued by our society. Gardner
is surely correct in noting that we tend to focus too much on the
skills and capacities that help people succeed in school. Whether or
not these other abilities are forms of intelligence, they are still
abilities to be highly esteemed and, if at all possible, nurtured and
developed. The cultural context of intelligence. Investigations
on practical intelligence and on multiple intelligences point up
certain limitations of standard intelligence tests. These limitations
become more glaring when trying to assess intelligence in members of
other cultures. To begin with, many standard intelligence tests
emphasize quick and decisive responses. But not all cultures share
Western preoccupation with speed. Indians and Native Americans, for
example, place a higher value on being deliberate; in effect, they'd
rather be right than quick. In addition, they prefer to qualify, or to
say "I don't know" or "I'm not sure," unless they're absolutely certain
of their answer. But such deliberations and hedging won't help their
test scores; on standard intelligence tests you get more points if you
guess . All
of this makes it clear that we have to be very careful in applying
intelligence measures. Intelligence tests do capture important aspects
of intellectual functioning, but they do not capture all aspects or all
mental abilities. Intelligence-test
performance seems to be determined by both environmental and genetic
factors. Evidence for the role of genetic factors comes from the fact
that the correlation between IQs of identical twins is higher than that for fraternal twins
and that this correlation is remarkably high even when identical twins
are reared apart. Further evidence for a hereditary contribution comes
from adopted children whose IQs correlate more highly with those of
their biological than their adoptive parents. Evidence for
environmental effects is provided by increases and decreases in the
mean IQ of populations whose cultural or educational level has risen or
fallen. Environmental effects may also explain a worldwide improvement
in IQ scores. A similar point is made by adoption studies that show
some correlation in IQ between children and their adoptive parents. In
recent years, much interest (and polemic) has focused on IQ differences
among racial-ethnic groups. The mean IQ of American blacks is about 10
to 15 points lower than that of American whites. Some authors have
argued that this is in part a consequence of a genetic difference
between the two groups. Environmentalists reply that the difference is
markedly reduced by various environmental changes such as interracial
adoption. A similar point is made by the fact that the mean IQs of
children of white German mothers fathered by U.S. soldiers after World
War II are just about the same whether the fathers were black or white.
It is also supported by the fact that IQ is more closely related to the
phenotype of dark skin than it is to the genotype. Questions and tasks on main topics . 1.What does intelligence test measure? 2. What is the idea of theory of multiple intelligence ? 3.How do researchers study the role of genetic factors in intelligence investigations?
Table 1.Characteristics of the mentally retarded. Degree of retardation | IQ range | Level of functioning at school age(6-20 years) | Level of functioning in adulthood (21 years and over) | Mild | 50-55 to approx 70 | Can learn academic skills up to approximately sixth-grade level by late teens; can be guided toward social conformity. | Can usually achieve social and vocational skills adequate to maintain self-support, but may need guidance and assistance when under unusual social or economic stress. | Moderate | 35-40 to 50-55 | Can profit from training in social and occupational skills; unlikely to progress beyond second-grade level in academic subjects; may learn to travel alone in familiar places. | May achieve self-maintenance in unskilled or semiskilled work under sheltered conditions; needs supervision and guidance when under mild social or economic stress. | Severe | 20-25 to 35-40 | Can talk or learn to communicate; can be trained in elemental health habits; profits from systematic habit training. | May
contribute partially to self-maintenance under complete supervision;
can develop self-protection skills at a minimum useful level in
controlled environment. | Profound | below 20-25 | Some motor development present; may respond to minimal or limited training in self-help. | Some motor and speech development; may achieve very limited self-care; needs nursing care. |
Source: Psychology, after H. Gleitman, 1998 p. G38. Theme 7. Emotional Experience.The main topics. 1.The James-Lange theory. 2.The attribution-of-arousal-theory. 3 Emotional behavior : facial expressions. 4.Basic and universal emotions. 5.Culture and emotions. THE JAMES-LANGE THEORY, THE ATTRIBUTION-OF-AROUSAL THEORY Some
features of emotion, such as our gestures and expressions, are public
and can readily be studied. Our physiological responses can also be
studied using electronic monitors. But it is unknown how our emotions
are experienced subjectively, the way we feel “inside”. In
nineteenth century psychologists tried to catalog various emotional
experiences such as they had classified the different sensations
provided by the senses .
But their efforts were not very successful. Another approach to the
problem was proposed by William James. To James, the crucial facet of
emotion was that it is an aspect of what a person does. In fear we run; in grief we weep. The interpretation
is that the behavior is caused by the emotion. James stood common sense
on its head and maintained that the causal relation is reversed; we are
afraid because we run. This ideas are now known as the James-Lange theory of emotions. (Carl
Lange was a European contemporary of James who offered a similar
account). The theory asserts that the subjective experience of emotion
is neither more nor less than the awareness of our own bodily changes
in the presence of certain arousing stimuli. Such bodily changes might
consist of skeletal movements (running) and visceral reactions
(pounding heartbeat), although later adherents of the James-Lange
theory emphasized the visceral responses and the activity of the
autonomic nervous system that underlies them. An
alternative theory focuses on cognitive factors. Emotional experiences
are usually initiated by external events - a letter with tragic news, a
loved one’s return, a job failure. Events such as these bring grief,
joy, dejection, or humiliation, but before they can possibly affect us
emotionally they must be appraised and understood. Stanley
Schachter and Jerome Singer combine a cognitive approach with bodily
feedback to explain emotion. According to Schachter and Singer’s attribution-of-arousal theory (sometimes called cognitive arousal theory)
various stimuli may trigger a general state of autonomic arousal, but
this arousal will provide only the raw materials for an emotional
experience . This state of undifferentiated excitement is shaped into a
specific emotional experience by cognitive appraisal and interpretation. According
to the attribution-of-arousal theory, emotional experience is produced
not by autonomic arousal as such, but rather by the interpretation of
this arousal in light of the total situation as the person understands
it . The role of the amygdala in emotional appraisal In there study Schachter and Singer had
provoked considerable criticism and, like many claims about emotion,
remains controversial . Their theory reminds us that our conception of
emotion must include at least two elements - the bodily arousal itself
and the cognitive appraisal of the circumstances attending that
arousal. Some recent studies of the brain suggest that, while all
levels of the brain from the hindbrain to the neocortex appear to be
involved in emotion, a single structure - the amygdala - is
largely responsible for integrating arousal with appraisal. The
amygdala is well situated in the temporal lobe to perform this
integrative role, receiving input from diverse areas of the brain,
including sensory areas of the cortex and relay centers for sensory
information in the thalamus . Studies in 1937 conducted by Kluver H. and Bucy P.C. with humans and animals
support the contention that the amygdala plays a central role in
stimulus appraisal, tagging stimuli with their emotional or
motivational significance. Thus, monkeys who had their amygdalas
removed could recognize objects normally but could not distinguish what
they were for: They would try to eat a block of wood or to touch a
lighted match . Patients with damage to the amygdala do not acquire
conditioned fear responses, even though they can (calmly) recall which
visual or auditory stimuli were paired with the unconditioned stimulus . In
short all of these findings support the claim that the amygdala is
essential in identifying the emotional significance of a stimulus with
important consequences for our subsequent reactions to that stimulus. Emotional Behavior: Facial Expressions. Humans
have a number of expressions associated with emotion, many of them
conveyed by the face. Our expressions - our smiles, frowns, laughs,
gapes, grimaces, snarls and winks - are intimately tied to our social
lives, and these facial expressions have been of special concern to
psychologists studying emotion. Much
of our current interest in facial expressions is due to Charles Darwin
(Darwin, 1872 ), who hypothesized that humans possess a set of
universal facial expressions that are vestiges of basic adaptive
patterns shown by our evolutionary forerunners. For example, our
“anger” face, often expressed by lowered brows, widened eyes, and open
mouth with exposed teeth, reflects the facial movements our ancestors
would have made when biting an opponent. Similarly, our “disgust” face,
often manifested as a wrinkled nose and protruded lower lip and tongue,
reflects how our ancestors rejected odors or spit out foods. Darwin
noted their similarities to many of the displays made by monkeys and
apes, and believed that the expressions would be identical, reflecting
identical emotions among humans worldwide even “those who have
associated but little with Europeans” . To support this universality thesis,
Darwin conducted one of the first cross-cultural studies, sending
questionnaires to his colleagues in Europe as well as missionaries and
other contacts in the Far East. In their answers to his questions
Darwin’s respondents provided many cases that suggested the
universality of facial expressions. But Darwin’s evidence was not
authentic, and only in the 1960s did psychologists begin to test the
universality thesis across cultures using more rigorous experimental
methods. In
one of these authentic studies, American actors posed in photographs
designed to convey emotions such as happiness, sadness, anger, and
fear. The pictures were then shown to members of different cultures,
both literate (Swedes, Japanese, Kenyans) and nonliterate (members of
an isolated New Guinea tribe barely advanced beyond Stone Age culture),
and they were asked to pick the matching emotion label. In other cases
the procedure was reversed. For example, the New Guinea tribesmen were
asked to portray the facial expressions appropriate to various
prototypical situations such as happiness at the return of a friend,
grief at the death of a child, and anger at the start of a fight .
Photographs of their performances were then shown to American college
students who were asked to judge which situation the tribesmen had been
asked to convey (Ekman and Friesen, 1968) . When
given photographs of facial expressions and asked to supply the
appropriate emotion term, participants worldwide - even those in
relatively isolated cultures - do reasonably well . The same is true if
participants are asked to describe an emotionally tinged situation that
might have elicited the expression shown in the photo. But their
success depends in part on the particular facial expression they are
shown. Smiles - which are generally matched with “happy” terms and
situations - produce much greater consistency in identification than
all the other expressions . CULTURAL VARIATIONS IN FACIAL EXPRESSIONS It
is clear that the public use of facial expressions is affected by
culture. For example: Melanese chieftains frown fiercely when greeting
each other at a festive occasion, and Samurai mothers are said to have
smiled upon hearing that their sons had fallen in battle . Emotion differences may reflect cultural display rule.
So far we have treated facial expressions as though they were the
natural and spontaneous outcome of an underlying emotional state. That
is not to say that we can’t hide or fake an emotional reaction, but, in
general, when we are happy we smile; when sad we cry. Some researchers
contend that our facial expressions are primarily communicative displays
that are not so much a revelation of an inner state as they are a
message to others about actions we may take or wish others to take. Basic and Universal emotions. Many theorists sopose that several basic emotions underlie the wide range of emotions that humans are able to experience and that the complex emotions we feel are composites of the basic emotions. Others question the existence of basic emotions pointing to the fact
that lists of so-called basic emotions vary from researcher to
researcher and that supporters don’t agree on what makes an emotion
“basic”. Complex emotions are those that require a high level of
symbolic processing. Some depend on the judgments that a bad outcome
was controllable (anger) or that
it was not (pity). Others depend on the construction of cognitive
scenarios that involve what might have been (regret).Still others
depend on an “ as if “ experience, such as the emotions we feel while watching a theatrical performance Basic
emotions are generally assumed to be closely tied to our biology -
rooted in our evolutionary past and shaped by hard-wired patterns in
our nervous system. If so, then basic emotions are a trait of our
species and should be found in all cultures. It is notable that the
common lists of “basic” emotions used in cross-cultural research were
all constructed by Westerners, because, in fact, cultures differ widely
in their emotion lexicons - the
vocabularies available to describe emotions. Obviously, the words used
by different peoples to denote emotions may tell us little about their
inner, emotional lives. But if certain emotions are truly basic and
universal, then one might expect all cultures to share roughly the same
categorization of emotions. Across cultures one finds no common list of
basic emotions. Some cultures appear to have no words for emotions that
many Westerners consider basic; thus, the people who live on the
western Pacific Island of Ifaluk lack a word for surprise, and the
Tahitians lack a word for sadness. Other cultures have words that
describe common emotions for which we have no special terms. Thus, the
Ifaluk often feel an emotion they call fago,
which involves a complex mixture of compassion, love and sadness
experienced in relationships in which one person is dependent on the
other. And the Japanese report a common emotion called amae, which is a desire to be dependent and cared for . The German language reserves the word Schaden-freude for the special pleasure derived from another’s misfortune. Questions and tasks on main topics . 1 What is the difference between the James-Lange and Sachachter-Singer theories of emotions? 2 What is the amygdale’s role in emotional appraisal? 3 How did Ch Darwin explain the emotional processes in human? 4.What is the difference between basic emotions and complex emotions? REFERENCES 1.Bernstein, D.A., Roy, E.J., Srull ,T.K., Wickens ,C.D. 1988. Psychology. Boston etc.: Houghton Mifflin, cop., 704. 2.Corkin,S.
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