Transcript Ch11a

Psychology at the Dawn of the
20th Century
• Overview
– 1892-1923: Structuralism dominated American
psychology and was first supplemented and
then replaced by Functionalism
– 1924: Titchener conceded that Watsonian
Behaviorism had engulfed the United States
– 1930: Other varieties of behaviorism emerged
The Stages
1. 1913-1930: Watsonian Behaviorism
2. 1930-1960: Neobehaviorism
• Core of psychology is the study of learning
• Most behavior can be accounted for by the
laws of conditioning
• Psychology must adopt the principle of
operationism (operational definitions)
3. 1960-present: Sociobehaviorism and the
return to cognitive processes
Non-Watsonian Behaviorism
• Karl S. Lashley (1890-1958)
– Watson’s student
• Trained rats and then sliced their brains.
– Law of Mass Action
– Principle of Equipotentiality
• Cortex is complicated and learning cannot
be explained by simple Point-to-Point
connections
• Actually confirmed Watson’s claim for the
value of objective methods in psychology
Operationism ( or Operational Positivism)
• Percy W. Bridgman (1882-1961)
– Physicist who promoted operationism
within physics (Nobel Prize 1946)
– Psychologists followed (at least
through the 1920s-30s)
• Make the language of science objective:
– Instead of “hunger” state that the
animals were deprived for 24 hrs.
– Consciousness has no place in
scientific psychology; It can’t be
measured!
Neobehaviorism
• Edward C. Tolman (1886-1959)
– Left MIT to study with Koffka
• Gestalt background
– Landed at U.C. Berkeley
– 1912: studies with Koffka
– Dissatisfied with Watsonian
Behaviorism
– Developed Purposive Behaviorism
Edward C. Tolman
• Professional experience
– Instructor at Northwestern University
– 1918 hired by the U. C. at Berkeley
• Taught comparative psychology
• Conducted research on learning in rats
• Formed his own form of behaviorism after
becoming dissatisfied with Watson's
– During WWII was the office of strategic
services (OSS), which later became the central
intelligence agency (CIA)
Purposive Behaviorism
• How can one measure Purpose?
– Behavior “reeks” of purpose
– Learning is evidence of purpose
– Intervening variables are the actual
determinants of behavior
• S-R substituted with S-O-R
• S-Hunger-R
Purposive Behaviorism
• Rejected Thorndike’s Law of Effect
– Reinforcement has little to do with
learning
– Repetition helps an animal
understand the link between
environment and expectations.
These links are Sign Gestalts
– A rat in a maze makes choices based
on expectations. When an
expectation is confirmed, a Sign
Gestalt is strengthened.
Purposive Behaviorism
• Maze Experiments
– Rats completed mazes with the help of cognitive
maps, not by following a sequence of movements
– Vary starting point – Rat still gets cheese!
– Expectations could be modified
Purposive Behaviorism
• The attribution of purpose to behavior was
criticized by Watsonian behaviorists
because it implied the existence of
conscious processes
• Tolman responded that whether or not
presence or degree of organisms were
conscious was not relevant to him or did it
affect behavioral responses
• Central focus was overt responses
Purposive Behaviorism
Intervening variables
• The initiating causes as well as the results
of behavior must be observable and
operationally defined
• Causes are independent variables
–
–
–
–
–
Environmental stimuli
Psychological drives
Heredity
Previous training
Age
Purposive Behaviorism
Learning theory
• Learning was central in Tolman’s purposive
behaviorism.
• Rejected Thomdike's law of effect
– Reward has little influence on learning
– Proposed a cognitive explanation of learning in
its place
Behaviorism in Sum
• A forerunner of the cognitive movement
• Intervening variables
– Engendered scientific respect for operationally
defining internal states
– A necessary and useful format for dealing with
hypothetical constructs used by Guthrie, Hull,
and Skinner
The Age of the Rat
• The rat as an important research subject
• 1930’s-1960’s primary subject for
neobehaviorists
• Assumption that one could generalize
from rats to other animals and humans
• Simple, easy to study, readily available
Clark Leonard Hull (1884-1952)
• Hull’s life
– Ill health
– Poor eyesight
– Polio at age 24
– Meet challenges with
persistence and resolve
– Intense motivation to achieve
Clark Leonard Hull (1884-1952)
– University of Wisconsin (Ph.D. 1918):
studied engineering before psychology
– Early work revealed continued interest in
using objective methods
• Concept formation
• Effects of tobacco on behavioral efficiency
• Applied area: Aptitude Testing (1928)
• Practical methods of statistical analysis
• Invented a machine for calculating
correlations
• Hypnosis and Suggestibility (1933)
Clark Leonard Hull (1884-1952)
• 1929: research professor at Yale
• Interested in developing a theory of behavior
based on Pavlovian conditioning
– 1930’s articles about basic conditioning and its
usefulness in understanding complex higherorder behaviors
• Principles of Behavior (1943), a theoretical
attempt to account for all behavior
• A Behavior System (1952), the final form of
Hull’s theory
The Spirit of Mechanism
• Omitted mentalistic terms, including
consciousness and purpose
• Used mechanistic terms
• Human behavior
– Mechanistic, robotic
– Automatic
– Reducible to the language of physics
• Machines could be constructed that
would display human cognitive
functions
Drive Theory
• Drive
– An intervening variable
S>D>R
– a “stimulus arising from a state
of tissue need that…activates
behavior”
– Drive reduction is the only
basis of reinforcement
Drive Theory
• Drive strength is empirically
determined using key
characteristics of the environment
or of the resulting behavior
• Length of deprivation
– Intensity, strength, and energy
expenditure of the behavior
– Hull emphasized the latter measure
of response strength
Drive Theory
• Reinforcement: reduction or satisfaction of
a drive
• Primary drives: arise from a state of
physical need and are vital to the organism’s
survival
• Secondary drives
– Are learned
– Are situations or environmental stimuli
associated with the reduction of primary drives
– As a result of the association with primary
drives, become drives themselves
• SER = SHR x D x V x K
– SER : Potential for action
• Will you smoke the cigarette?
– SHR : Habit strength
• How long have you been smoking?
– D : Drive strength
• How long since last smoke?
– V : Stimulus intensity dynamism
• Is anyone else smoking?
– K : Incentive motivation
• Are there rewards or consequences?
Law of Primary Reinforcement
• “When a stimulus-response relationship is
followed by a reduction in a bodily need, the
probability increases that on subsequent
occasions the same stimulus will evoke the
same response”
– Reinforcement defined in terms of the reduction of
a primary need
– Primary Reinforcement (reduction of a primary
drive) is the basis for learning
– Secondary Reinforcement (reduction of a secondary
drive)
Law of Primary Reinforcement
• Habit Strength: the strength of the S-R connection
– A function of the number of reinforcements that have
occurred
– Refers to the persistence of the conditioning
• Learning cannot occur without reinforcement
– Reinforcement necessary for drive reduction
– Hull’s system as ultimately based on need-reduction is
contrasted with Tolman’s cognitive approach
Comment on Hull
• Experienced the same type of attacks as those
directed at Watson and other behaviorists
• Pronounced effect on psychology through
– The amount of research generated and provoked
– The achievements of his students and followers
– Defending, extending, and expounding objective
behaviorism
• Called a “theoretical genius”
Burrhus F. Skinner (1904-1990)
• One of the most influential
psychologists in the 20th
century
– Beginning in 1950’s, the
major embodiment of
behaviorism
– Large and loyal group of
followers
B.F. Skinner (1904-1990)
• Developed and wrote about subjects
that had considerable impact
–
–
–
–
Behavioral control
Behavior modification
Utopian society (Walden Two)
Beyond Freedom and Dignity, a
national bestseller
• Became a celebrity in his own right
B.F. Skinner (1904-1990)
• Skinner’s life
– Built things as a child and worked with and
observed animals
– Used his early life experiences as a base for his
system of psychology
– A product of past reinforcements
– Seemingly predetermined, lawful, and orderly
B.F. Skinner (1904-1990)
• 1925: Hamilton college (NY): degree in English,
no courses in psychology, phi beta kappa
• Worked at writing for two years after favorable
feedback from Robert Frost
• Depressed by lack of success as a writer Read
about Pavlov's and Watson's experimental work
• 1931: PhD from Harvard
B.F. Skinner (1904-1990)
• Dissertation: a reflex is a correlation between S and R
• 1938: The Behavior of Organisms; Covered basic
points of his system
• 1953: Science and Human Behavior; Basic textbook
for his system
• Toward end of life
–
–
–
–
Lived in a controlled environment
Enjoyed writing: a source of positive reinforcement
Published “Intellectual Self-Management in Old Age”
Described his feelings of dying with leukemia in a radio
interview
B.F. Skinner (1904-1990)
• 1990: vigorously attacked the growth of
cognitive psychology in a paper delivered at
the Boston meeting of the American
Psychological Association
• 1990 (final article): “can psychology be a
science of mind?”
• Died in 1990 at the age of 86
Skinner’s Behaviorism
• Devoted to the study of responses
• Concerned with describing behavior rather
than explaining it
• Dealt only with observable behavior
• No presumptions about internal entities
– The “Empty Organism” approach
– Internal physiological and mental events exist
but not useful to science
Skinner’s Behaviorism
• Single-subject design
– Large numbers of subjects not necessary
– Statistical comparisons of group means not
necessary
– A single subject provides valid and replicable
results
• Cannot predict behavior of a particular individual
from knowledge of the average individual
– Journal of the experimental analysis of behavior
established because mainstream journals did
not accept an N of 1.
Operant conditioning
• Contrasted with respondent (Pavlovian) conditioning,
which is elicited by a specific observable stimulus
• Operant behavior
– Occurs without an observable external stimulus
– Operates on the organism’s environment
– The behavior is instrumental in securing a stimulus
such as food
– More representative of everyday learning
– Most effective approach to science of behavior: the
study of the conditioning and extinction of operants
Operant conditioning
• Studied bar pressing in the plexiglas “skinner
box”: the rate of response
• Law of acquisition: “the strength of an operant
behavior increases when it is followed by the
presentation of a reinforcing stimulus”
– Key variable: reinforcement
– Practice provides opportunities for additional
reinforcement
• Thorndike and Hull: explanatory
• Skinner: strictly descriptive
Skinner Boxes
Could be programmed and automated!!!
Research Foci
1. Role of punishment in response acquisition
2. Schedules of reinforcement
3. Extinction of operants
4. Secondary reinforcement
5. Generalization
Subjects included humans as well as animals
Reinforcement Schedules
• Reinforcement is necessary in operant behavior
and can be delivered on different Schedules.
• Continuous Schedule: Pellet for every push
– Fast acquisition and fast loss of behavior
• Partial Schedule
– Fixed or variable time of delivery or rate
• Slower acquisition and slower loss
– Ratio (of responses)
• Fast learning as long as ratio isn’t too high
Is Conversation Operationally
Conditioned?
• Sounds made in speech are a type of behavior
– Can be reinforced by other sounds or behavior
– Listener controls speaker’s subsequent behavior
through reinforcement or punishment
Inventions and Public Profile
• Aircribs
– Mechanized environment
invented to relieve menial labor
– Not commercially successful
– Daughter reared in it with no ill
effects
Teaching Machine
• Teaching machine
– Invented in the 1920’s by Pressey
– Not enthusiastically received
• Surplus of teachers
• No public pressure to improve
learning
• Promoted by Skinner in the 1950s
– Better reception, but computers were
ready for applications
– Technology of Teaching (1968)
Pigeon Missile
• Pigeon-guided missiles
– Developed by skinner during WWII
– They Worked!
– Military wasn’t impressed.
Walden Two (1948)
• Novel of a 1,000-member rural community
• Behavioral control through positive
reinforcement
• Outgrowth of skinner’s midlife depression,
expressing his own conflicts and despair
• Reflected mechanism of Galileo, Newton,
and the associantionists
Applied Psychology
• Behavior modification through positive
reinforcement is alive and well
• Operant conditioning is widely used in
psychiatric hospitals and Business
• Research emphasizes the effectiveness of
reinforcement over punishment (most of
the time)
Criticisms of Skinner’s Behaviorism
• His extreme positivism
• His opposition to theory and willingness to
extrapolate beyond the data
– Grand predictions about society based on a
single rat?
• His position that all behaviors are learned
– Instinctive drift could ruin an animal show
• His position on verbal behavior
– Chomsky argues for an inherited ability to construct
sentences
Criticisms of Skinner’s Behaviorism
• ". . . There is no reason," he declares, "why
progress toward a world in which people may be
automatically good should be impeded." No
reason at all - provided you are willing to view
yourself as a baby, a retardate or a psychotic.
– Ayn Rand reviewing Beyond Freedom and Dignity
Skinner’s Contributions
• Contributions of Skinner’s Behaviorism
– Operant conditioning works!
– Reinforcement schedules follow Skinner’s laws
– Shaped American psychology for 30 years
– His goal: the improvement of society
– Strength and ramifications of his radical
behaviorism
Sociobehaviorism
– Social learning or sociobehaviorist
approach
• Stimulated by many, including some
behaviorists
• Reflected the broader cognitive revolution
in psychology
– 1995: consciousness overtly and
publicly returned to psychology
Albert Bandura (1925-)
• Background
– Experience with the psychopathology of
ordinary life
– 1952: PhD from the university of Iowa
– 1981: APA distinguished scientific
contribution award
Albert Bandura (1925-)
• Social cognitive theory
– Behavioristic
• Less extreme than skinner’s
behaviorism
• Reflects current zeitgeist in its
interest in cognitive variables
– Research focus: observation of the
behavior of humans in interaction
– Emphasizes the role of reinforcement in
learning and behavior modification
Albert Bandura (1925-)
– Cognitive aspect stresses the influence
of thought processes on external
reinforcement schedules
– Reactions to stimuli are self-activated,
person-initiated rather than automatic
– Reinforcer effective if
• Person is consciously aware of what
is being reinforced
• Person anticipates the same
reinforcer if the behavior is repeated
– Vicarious reinforcement: learning “by
observing how other people behavior
and seeing the consequences of their
behavior” rather than directly
experiencing the consequences of
one’s own
– Assumes human capacity to anticipate
and appreciate those outcomes
– One can regulate one’s behavior by
• Imagining those consequences, and
• Making a conscious selection of the behavior to
manifest
– Is like the S-O-R model, with O being
equal to cognitive processes
• Cognitive processes distinguish
Bandura’s views from skinner’s
– Who/what controls behavior?
• Skinner: whoever controls reinforcers
• Bandura: whoever controls the models in a
society
Behavior modification
– Bandura’s goal: change or modify
socially undesirable behavior
– Focus: external aspects of abnormality,
i.E., Behavior
– The use of modeling
– Bandura’s form of behavior therapy is
widely used in diverse settings and has
strong research support
Comment
– Criticized by traditional behaviorists who
deny cognitive processes
– Positive aspects of Bandura’s theory
• Widely accepted in psychology
• Consistent with the functionalism of
American psychology
• Objective
• Amenable to precise laboratory methods
• Responsive to the current cognitive
zeitgeist
• Applicable to practical problems
Julian Rotter (1916-)
• Background
– Grew up comfortably in Brooklyn
– Father lost his business in 1929 crash
• Turning point for the 13-year-old
• Triggered life-long concern for social justice
• Lesson on the effects of situational
conditions on personality and behavior
– Read Freud and Adler in high school
– Learned that jobs scarce in psychology
• Cognitive processes
– 1947: the first to use the term social
learning theory
– Cognitive approach to behaviorism
– Invokes the existence of subjective
experiences
– Criticized Skinner’s study of single
subjects in isolation
– Relies on rigorous, well-controlled
laboratory research
– Studies only human subjects in
social interaction
– Deals with cognitive processes more
extensively than Bandura
• Both external stimuli and the reinforcement
they provide affect behavior
– Four cognitive principles determine
behaviors
1. Expectation of amount and kind of
reinforcement
2. Estimation of probability the behavior will
lead to a particular reinforcement
3. Differential values of reinforcers and
assessment of their relative worth
4. Different people place different values on the
same reinforcer
• Locus of control: “beliefs about the source
of our reinforcers”
– Beliefs about the source of one’s
reinforcements
– Internal locus of control: belief that
reinforcement depends on one’s own
behavior
– External locus of control: belief that
“reinforcement depends on outside
forces such as fate, luck, or the actions
of other people
– Is learned in childhood from the ways
one is treated
• Comment
– Rotter’s theory attracts followers who
• Are experimentally oriented
• Think cognitive variables influence behavior
– A great many studies support his
theory, particularly regarding internal
and external locus of control
The fate of behaviorism
• Cognitive challenge to behaviorism from within
modified the behaviorist movement
• Sociobehaviorists still consider themselves behaviorists
– Are called methodological behaviorists because they
employ internal cognitive processes
– Are contrasted with radical behaviorists like Watson and
skinner who do not deal with presumed internal states
• Skinnerian behaviorism peaked in the 1980s
• Declined after skinner’s death in 1990
• Today’s behaviorism, particularly in applied
psychology, is different from forms it took from 1913
(Watson) to 1990 (skinner)
• In an evolutionary sense, the spirit of behaviorism still
lives
Bandura et al., 1961