Download doc psych 100 review summary

Gage: UNPLEASANTNESS IN VERMOUTH (Damasio)

Phineas Gage, a construction foreman, hit by an iron rod

Iron rod enters from left cheek, pierces the base of the skull, traverses the front of the brain and exits
through the top of the head.

Gage is pronounced cured in less than two months.

But….“Gage is no longer Gage” .

Brain includes personal and social dimensions of reasoning.

Some part of the value system remains but is unconnected to real-life situations.

Intact attention, perception, memory, language, intelligence. “Dissociation”.

Two camps of thought:
o
If brain produces the mind, it does it as a whole and not as collection of parts with special functions
o
Brain has specialized parts that generate separate mind functions.
o
Brain an aggregate of many organs, each having a specific physiological faculty e.g. Benevolence and
Venerance.
o
Damasio: “What determines the contribution of a given brain unit to the operation of the system to which it
belongs is not just the structure of the unit but also its place in the system.

Can Gage be held responsible for his behavior?
PENFIELD AND ROBERTS

Consciousness
o
William James: constant flow, constant change.
o
In the awareness there is a succession of perceptions of the present.

Psychical Responses to Stimulation and Discharge:
o
Cerebral cortex has folds. Only about 35% on the surface.
o
Neurons and ganglion cells are responsive to electrical stimulation (as well as chemical stimulation—
drugs).
o
Behavioral functioning of a brain area is revealed due to conductivity (Sensory or motor areashommunculus).
o
Penfield and Roberts first used this electrical stimulation technique to examine the temporal lobe as
treatment for epilepsy
o
The goal of the electrical exploration of the temporal lobe was to find the epileptic locus and surgically
remove it. Stimulation of the epileptogenic focus induces a partial seizure.
o
Hughlings Jackson was the first to observe that patients undergoing electrical brain stimulation experienced
a state of reminiscence or double-dissociations which he calles “dreamy states”.
o
Double- dissociations: a state where the patients re-live past experiences but are still aware of their present
conditions.
o
There are two types of physical responses that are obtained from electrical stimulation and each can be
mapped to a specific brain region
Interpretative: “Déjà vu” phenomenon (false memories)
False interpretations (called illusions).
Stereotyped Symptoms: judgments of familiarity, strangeness, distance, intensity, loneliness fear.
The subject becomes aware of the present and re-interprets it.
Experiental:
Characterized by flash-backs that have strong visual and auditory components. Not still pictures.
Consciousness is re-visited.
Double-consciousness (patients re-live past streams while being aware of the present)
They occur in an all or none pattern (don’t go backward, are not mixed with other experiences and stop as suddenly
as they started upon removal of the stimulation)
The same experience can be elicited by re-stimulating the same area. Lower threshold though.

Both of these types of responses argue for the existence of a permanent recording of the stream of
consciousness, which must be preserved in a specialized mechanism that allows for later recall.

These responses are specific to the temporal lobe
A PHYSIOLOGICAL THEORY by D. O. HEBB

Question: How come intelligence is intact despite surgical removal of a major portion of the brain?

Learning vs. Perception

Theory of cell assemblies attempts to bring together anatomical, physiological and behavioral data to
understand the integrative function of the whole brain.

o
PROBLEM OF PERCEPTION
As opposed to learning, not dependent on excitation of a particular set of neurons.
o
Learning is a changed pattern of conduction in the brain that results from experience and makes a change of
response potential.
o
If the pattern of conduction persists it is memory. Hence learning is a localized effect.
o
Not true for perception e.g. different angles of familiar objects.
o
Lashley-Kohler: what matters in perception is the Gestalt, the form or pattern of stimulation.
o

o
But how can variable perception excite a specific response? Hologram
DEVISING AN IMPROBABLE THEORY:
Set (attention, attitude, expectancy) is brain activity that is free from sensory control (Hilgard and Marquis)
o
Lashley showed that direct connections (of learning) do not occur. For e.g. (Figure 14.2) connection
between the visual and motor cortex.
o
Lorent de Neo showed that cortex is mostly composed of very complex closed or re-entrant pathways
o
According to Hebb “set” occurs when two stimuli are presented one after the other and the response to the
second is controlled or modified by the first.
o
The cell assembly theory explains set: The mechanism of thought is a recurrent neural loop that received
sensory input from another loop but that can be maintained in the absence of sensory information.
o
Brodgen’s experiment: dogs can form purely sensory associations.
o
Hebb thought that self-re-exciting system must have a number of circuits because of fatigue and for mass
excitation
o
But…this theory does not hold for visual perception. A different cell-assembly would be required for each
possible stimulus.
o
Perhaps cell assemblies formed for representation of fundamental parts. However, for unfamiliar objects
new cell-assemblies would have to be created.
o
Support:

Blind people

Chimpanzees raised in the dark

Head of a Chimpanzee

EXPERIMENTAL TESTS: THE EARLY ENVIRONMENT
o
Effects of environment on intelligence
o
Importance of period of growth (Hymovitch)
o
Exposure to visual stimuli (Hymovitch)
DIRECT PERCPETION OF REMOTE GEOGRAPHICAL LOCATIONS

Experiments on remote-viewing trials.

Remote viewing: the ability of certain individuals to access and describe, by mental processes, remote
geographical sites blocked from ordinary perception by reason of distance and shielding

A series of 5 experiments were conducted

Experimenter is stationed at a remote city from the subject claiming to be capable of ESP.

A phone conversation between the two initiated the experiment

The experimenter then had to travel to a remote location unbeknown to the subject

The experimenter was instructed to produce written real life impressions of his/her experience

The subject was asked to produce the same impressions in real time as well.

A 3rd experimenter later scored the statements in the reports based on main concepts (scale of 0 to 10)

The results show evidence for remote-viewing in most cases. The authors thus argue that this is evidence of
real-time remote viewing.
HYPNOSIS
HISTORICAL BACKGROUND:
o
Franz Anton Mesmer:

Animal magnetism.

Committee set by the King of France discredited him.

Used modern physical science.

Importance of imagination. Suggestibility.

Mesmerism was used to treat various ailments ranging from simple headaches to curing invalids. Also used
for inducing anesthesia during surgeries.
o
James Braid:

Coined the term ‘hypnotism’ to refer to ‘nervous sleep’

Used in his medical practice
o
Jean-Martin Charcot:

Hypnosis was hysterical (a neurological phenomenon)

Observed in people suffering from abnormality of the nervous system.
o
The Nancy School:

A normal phenomenon attributed to suggestion.
o
Freud: Used it briefly and successfully in psychotherapy. But rejected it later in favor of free association
and psychoanalysis.

Hypnosis vacillated between popularity and taboo.

Used during wars to treat ‘shell shock’ syndrome (PTSD). Quicker results than other psychotherapy
methods.

British and the American medical associations allowed training in hypnosis. Research laboratories were
established at some leading universities.
HYPNOTIC RESPONSIVENESS:

Individuals vary in their susceptibility to hypnosis.

Low inter-investigator reliability due to lack of standard measurements.

Hypnotic Induction Tests:
o
Eye closure method.
o
Hand Levitation method.

Hypnotic Responsiveness Scale:
o
A series of tasks to test the depth of hypnosis level of a subject

Involuntary movement of hands (easy item)

Interlocking of fingers (hard item)

Age regression

Posthypnotic suggestions

Posthypnotic amnesia etc…
o
Score derived by adding the number of ‘items’ passed.
o
Individual subject scores are consistent independently of the hypnotist or test interval (time).
o
Scores tend to change with age
o
Changes due to subject or testing procedure (e.g. willing vs. reluctant subjects).

Can a person learn or be trained to be more responsive?
o
Not easy despite assumptions of practicing hypnotists.
o
Improvement small for the initially non-responsive subject.
o
General vs. Specific hypnotic Responsiveness.

No significant correlation between personality characteristics and hypnotic susceptibility.

Some indication of hereditary influence. (parent to child, MZ vs. DZ twins)

Imaginative involvement may be a factor. Measured by the ‘absorption’ scale.
PHYSIOLOGICAL EVIDENCE:

EEG: more hypnotizable the subject, the higher the proportion of time in EEG-Alpha

Preference of the right hemisphere (eye shifting) in right-handed people is correlated with high
hypnotizability scores.
STATE-NONSTATE ISSUE:

Disagreements are not over facts, but over conceptualizations.

Circular argument:
o
How can you tell that a subject is hypnotized—because he acts in a certain way
o
What causes the subject to act this way—the fact that he is hypnotized.

Trait vs. State
o
State: hypnosis is a change from the normal (support found in that hypnotic induction increases
responsiveness)
o
Trait: individual differences in hypnotic responsiveness.

‘Reals’ vs. ‘Instructed simulators’
o
Pain reduction
o
Posthypnotic tests outside the experiment
o
Speed in coming out of hypnosis
HYPNOTIC EXPERIENCE AND RELATION TO THE HYPNOTIST

Sense of relaxation (both mental and physical).

Narrowed attention.

Here-and-now experience.

Rich imaginative and fantasy experiences

Suggestibility (issue of control: not authoritarian, more like a helpful guide)

Depth may fluctuate widely within a single hypnotic session. Best measure of depth is verbal self-report
(on a scale)
o
Responsiveness takes place in the very low portion of the total scale of depth
At great depths, responsiveness to suggestion falls off
IMAGES AND PLANS

We Imagine what out day is going to be and make Plans to cope with it.

Psychology attempts to study the invisible and to find why behavior occurs. Discover recurrent patterns of
stimulation and response.

What an organism does depends on what happens around it.

2 schools of thought
o
Optimists:

A straight-forward stimulus-response relation.

Instances are reflex arc and Pavlovian conditioning.

Incorporate events (or stimuli) that occur before and after the response
o

Pessimists:
More complex beings

Stimulus and response mediated by an organized representation of the environment, the internal
representation of which is called a ‘schema’.

Criticism: Occam’s razor

maps
Tolman studied rat behavior. Believed could postulate from simple to more complex animals. Cognitive

Tolman was criticized in that his cognitive processes do not explain behavior. There is a gap between
knowledge and action.

Similar criticism of Wolfgang Kohler’s Chimpanzee study.

William James:
o
If form a clear image of an action, that action tends to occur.
o
Anything in between is not represented in consciousness.
o
Introspectively, therefore, there is no vacuum.
o
Unpleasant tasks? Feeling of effort arises from focusing attention.

But…..
o
How are actions controlled by the internal representation of the world?
o
Like actions, this internal representations of the world need to be organized in some sequence.
o
Goal directed actions can be classified into molar (large) vs. molecular (small) units.
o
Proper description of behavior must be made on all levels simultaneously.

Hierarchical organization of Behavior.
o
PLAN: Any hierarchical process in the organism that can control the order in which a sequence o`f
operations is to be performed.
o
STRATEGY AND TACTICS:


Molar corresponds to behavior strategy
Molecular corresponds to tactics.
o
EXECUTION: When a Plan is controlling the sequence of operations it is said that the Plan is being
executed.
o
IMAGE: All the accumulated, organized knowledge an organism has about itself and its world.
Authors wish to explore the relationship between the Image and the Plan. They are however not mutually exclusive.
PARASYCHOLOGY: FRONTIER SCIENCE
OF THE MIND
Parapsychology:

Parapsychology means psychical research

Part of natural sciences

Needs to be distinguished from:
o
Occultism: study of hidden arts or principles
o
Spiritualism: religious belief centered on the existence of a world of discarnate personalities that are able to
communicate with the living

Part of psychology because only concerned with living (behaving) organisms.

It deals with study of psychical phenomena

An occurrence that has been shown by experimental investigation to be unexplainable wholly in terms of
physical principles.
Extrasensory Perception (ESP):

Knowledge is acquired by a mode of perception that is independent of the senses.

events
Mental process called perception because knowledge conveyed in such an occurrence concerns external

Involves subject-object interaction: subject has the knowledge of an object.

Different kinds of ESP:
o
Telepathy: transfer of thoughts from one mind to another without the intermediation of the senses
o
Clairvoyance: Extrasensory perception of objects or objective events as distinguished from the mental
thoughts of another person
o
Precognition: Perception of a future event by means of ESP.
Psychokinesis (PK):

Occurrences in which some personal influence produces a physical effect without physical intermediation.

Involves subject-object interaction: The subject affects the object
Conclusion:

Different from purely psychological phenomena in that can be shown to be nonphysical in character.

Different from physical and physiological phenomena in that no physical explanation exists even though
physical objects and events are involved.
BEHAVIORISM, COGNITIVISM AND THE
NEUROPSYCHOLOGY OF MEMORY

What is learning?
o
Behaviorism: If a particular response to a particular stimulus elicits reinforcement it is likely that that
response will be repeated.
o
Cognitivism: Acquisition and storage of information, that new information can be combined with to lead to
new types of behavior.

Can both exist at the same time?
STUDIES OF LEARNING:

Thorndike’s ‘law of effect’. Connection between a stimulus and response

Skinner: reinforcement strengthens a response

Clark Hull: Habit : stimulus-response pairs strengthened by reinforcement

Tolman:
o
Organisms learn that particular responses lead to particular goals; they retain information, and that
information is confirmed, or not, by experience, resulting in learning.
o
Reinforcement develops expectancies about how certain goals can be reached.

Wolfgang Kohler:
o
Insight: discovery of relations among bits of stored information.

I. Krechevsky:
o
Animals, as well as people, capable of testing hypotheses.


Neuropsychological research has shown that there must be more than one system in the brain.
Two system-model:
o
System that stores memories (cognitive-can be known. Also called declarative or explicit memory )
o
System that develops habits (non-cognitive—Also called nondeclarative or implicit memory)
MEMORY AND THE BRAIN:

Memory: the ability to store sensory information for later retrieval as images, thoughts and ideas.

Stored neural representations of stimuli that can be first recognized and then connected to create
associations.

Use of brain damaged areas to study localization:
o
H.M. (severe epilepsy treated by surgery that caused bilateral damage to the medial part of the temporal
lobe—anterograde amnesia)
o
Monkey model: bilateral damage to the hippocampus, amygdala and underlying cortex (the rhinal areas)
impairs performance in “delayed nonmatching to sample task” (involving both touch and sight).
o
Other area that can cause amnesia is the diencephalon (a region at the very center of the brain). Includes
thalamus (medial portion) and mamillary bodies (as in Jimmy G.’s case)
o
Rhinal cortex extends fibers to medial thalamus and the orbital prefrontal cortex. The latter two are also
connected.
o
Sensory input  Higher-order sensory cortex  Rhinal cortex thalamus and frontal cortex
o
Rhinal /orbital prefrontal cortex  basal forebrain  higher-order sensory cortex.
o
Necessary for the storage of representations in the sensory area.

As little as one exposure needed

Representations become linked to one another by association.
o
Stored neural representation may be a combination of Robert Desimone’s single neuron findings:

Tuning: neurons can be tuned by perceptual experience to response to a shape or other sensation

Adaptive Filtering: use stored information to filer new information for similarities

Sustained activation: provide a mechanism for working memory

Association: pairing of different stimuli.
THE NONCOGNITIVE HABIT SYSTEM:

More than one retention system must be present because of the ability of patients with anterograde amnesia
to learn and retain certain tasks.

The ‘habit system’ -- neural correlate “extrapyramidal system” specifically the basal ganglia (caudate
nucleus, putamen and globus pallidus).

Circuit for habit formation involves the cortex, the striatum (includes the caudate nucleus and putamen) and
the motor-cortex areas.

Huntington’s chorea patients (dysfunction of the striatum) unable to do a mirror-reading task which
amnesics can do (habitual nature) but are able to do a verbal recognition task (requiring memory) that amensics fail.

Monkeys with medial-temporal-lobe damage (parallel to human amnesia) show rapid forgetting objectrecognition task when shown only once but can learn the task upon repeated exposure (habit formation) even when
interval b/w exposure is 24 hours.

Monkeys with medial-diencephalic lesions are impaired in object-recognition tasks but learn visual
discrimination as quickly as controls.

In rats the caudate nucleus seems to play an essential role.

Although ‘habit system’ may be the more primitive system of the two learning systems, it is not necessarily
simpler. More than one part of the brain may be implicated.

Other than these ‘Instrumental’ conditioned learning, habits may be formed by Classical or Pavlovian
conditioning. (the conditioned response (CR) to the formally neutral stimulus is an automatic or involuntary
response)

What is stored in the habit system? The probability that a stimulus will elicit a response (which is
determined by previously reinforced pairings).
o
It is not available to the consciousness.
o
It is a stimulus-response connection.
o
The response probabilities develop gradually as a result of repeated experience.

The main structure is likely to be a subcortical structure (mentioned above). If it is the striatum (caudate
nucleus and putamen) the neurotransmitter dopamine is likely to be involved.

Rescorla: Associations can be formed between
o
Stimulus and the Response  habit system
o
Stimulus and the Reinforcer  memory system
o
Response and Reinforcer  habit or memory depending on nature of task)
MEMORIES, HABITS AND LEARNING

What is learned may depend on how it is learned.

Different systems allow for different kinds of learning and are functionally independent of each other.

Behaviorist explanation appears to parallel the learning system utilized by the habit system.

Cognitive explanations appear to parallel most closely the processes active in the memory system.
GEORGE MILLER’S MAGICAL NUMBER SEVEN,
PLUS OR MINUS TWO

The number 7 keeps appearing in data so there must be something unusual about it (or he is suffering from
delusions!)

His studies start with experiment that tested how accurately people can assign numbers to the magnitudes
of various aspects of a stimulus (experiments in absolute judgement)

These results are analyzed in terms of information theory.

The concept of ‘amount of information’ is more advantageous than the concept of ‘variance as the former is
a dimensionless quality (not restricted to units of measurement) allowing us to use it in situations without a metric.

Higher the variance  more ignorant of situation  lot of information from observation

In a communication system there is a lot of variability about what comes into the system and what goes out,
in a good system, these two are highly correlated. The correlation is referred to as ‘transmitted information’ in this
chapter.

Graphically if there are two circles, one for the input and the other for output, then the overlapping areas of
the two circles shows the correlation (or covariance) between the input and output also called ‘transmitted
information’.

This model can be applied to experiments of absolute judgment
o
The input circle is in the information in the stimuli presented to the subject
o
The output is the amount of information in the subject’s responses
o
Study the effect that increasing the input has on the responses
o
If absolute judgment is accurate the increases in ‘input’ will all go into the ‘transmitted information’ and be
recovered from the subject’s responses.
o
Normally, with increases in input levels, the transmitted information increases at first and then eventually
levels off at some asymptotic value.
o
This value is the channel capacity of the observer.
o
A bit is the amount of information that is needed to make a decision between two equally likely
alternatives. (Two bits of information needed to make decision between four equally likely, and three bits to make
decision between eight equally likely alternatives and so on and so forth…)
ABSOLUTE JUDGEMENTS OF UNI-DIMENSIONAL STIMULI

Subjects asked to identify tones of different frequencies.

Subjects were never confused when only 2 or 3 tones used, with 4 confusion was rare, and with 5 or more
tones confusion was frequent.

2.5 bits of information (corresponding to 6 equally likely combinations) was found to be the channel
capacity.

This means that ‘no matter how many alternative tones we ask a subject to judge, the best he can be
expected to do is to assign the alternatives to six different classes without error’.

Experiments were also done to test absolute judgment in the case of loudness (2.3 bits), taste intensities
(1.9 bits), visual position (3.25 bits), square sizes (2.2 bits) and so on….

Thus, we possess a finite and rather small capacity for making unidimensional judgments which does not
vary a great deal from one sensory attribute to another.
THE ABSOLUTE JUDGMENT OF MULTI-DIMENSIONAL STIMULI:

This magical number 7 applies to one-dimensional judgments.

We identify several hundred faces, thousands of words and objects everyday.

Perhaps the difference is because the latter differ from one another in many ways. Results from different
experiments confirm this

Channel capacity of position of dot in a square is 4.6 bits, identification of saltiness and sweetness in a
solution is 2.3 bits (salt alone is 1.9), loudness and pitch of pure tones is 3.1, Colors varying in hue and saturation is
about 3.6 bits.

Still different from multidimensional stimuli we face in our everyday life.
One experiment which included six different acoustic variables in a tone showed a channel capacity of 7.2 bits.

Hence, addition of independently variable attributes to the stimulus increases the channel capacity, but at a
decreasing rate.

Evolutionary advantage?

On a different task, subjects had to report the number of dots present when any number of dots from 1 to
200 were flashed for 1/5 of a second.
o
Below seven dots, subjects were said to subitize (they made no errors!)
o
Above seven dots, subjects were said to estimate (similar to what used to be referred to as ‘span of
attention’).
THE SPAN OF IMMEDIATE MEMORY:

There is a clear and definite limit to the accuracy with which we can identify absolutely the magnitude of a
unidimensional stimulus. This limit is called ‘span of absolute judgment’.

Variety of techniques for getting around to it or increasing this limit from 7:
o
Make relative rather than absolute judgments;
o
Increase the number of dimensions along which the stimuli can differ (there may be a span of perceptual
dimensionality); and
o
Make sequence of several absolute judgments in a row.

For the last technique we can use an experiment on ‘immediate memory’ rather than ‘absolute judgment’.
For this the subject is asked to withhold response until several stimuli have been presented in succession.
o
o
Immediate memory is limited by the number of items (and not by the amount of information).
Difference between ‘bits’ of information and ‘chunks’ of information.
RECODING:

Since the memory span is fixed by number of chunks (and not bits) we can increase the number of bits of
information simply by building larger and larger chunks.

This process in communication theory would be called recoding.

From many chunks with few bits recode input into fewer chunks with more bits per chunk.
o
Morse code—first hear dots and dashes, then letters, then words and then whole sentences. The chunk size
successively increases.
o
People can repeat back 8 decimal digits, but only 9 binary digits.

Increasing the chunk size by recoding the digits increases the number of binary digits retained.
o
Everyday example would be when we translate a story into our own words to remember it better. Upon
recalling details are recreated in a manner consistent with the verbal recoding we had made.
This may explain in part, the inaccuracy of eye witness testimony