Behaviorism: After the founding

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Chapter 11

• Behaviorism After the founding

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The Neobehaviorists
Edward Tolman (1886-1959) Clark Hull
(1884-1952) Edwin Guthrie (1886 - 1959) B. F.
Skinner (1904-1990)
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Basic Points of Agreement

• The core of psychology is the study of learning
• Most behavior, no matter how complex, can be
  accounted for by the laws of conditioning
• Psychology must adopt the principle of
  operationism

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Operationism
Concepts should be defined in terms of the
operations or procedures used to measure them.
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Operationism
Concepts should be defined in terms of the
operations or procedures used to measure them.
What are some examples of operational definitions?
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Some Ideas Associated with Tolman

• Behavior is purposive
• Organisms learn expectencies (rather than
  responses)
• Organisms acquire cognitive maps of their
  environment

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Some Important Findings of Tolman

• Place learning
• Latent learning
• Insight

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Tolmans use of intervening variables
Tolman began a tradition of using intervening
variables as part of a theory.
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Tolmans use of intervening variables
Watson was considered an S - R psychologist.
Tolman believed that a number of variables
intervened between the stimulus and response.
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Tolmans use of intervening variables
Example Whether an organism responded or not
depended on the level of demand. Demand was a
function of the maintenance schedule.
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Tolmans use of intervening variables
Sometimes Tolmans approach is referred to as
S-O-R psychology.
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A Question about Tolman
Was Tolman a behaviorist or a cognitivist?
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Clark Hull
1882 - 1952
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A brief personal history

• Grew up in Michigan.
• Taught school before he completed high school
• Attended college with the idea of pursuing
  mineral engineering
• After contracting polio he switched to psychology
• Completed his undergraduate degree at the
  University of Michigan
• After time as a school teacher, he completed his
  Ph.D. at U. of Wisconsin in 1918

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A brief personal history contd

• Joined the faculty at Wisconsin
• Left for Yale University in 1929
• By 1950 he was the most widely cited psychologist.

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Hulls Hypothetico-deductive approach to theory
Hulls approach to theory was modeled after
geometry. Through the application of various
postulates and theorems one could derive testable
predictions about behavior.
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Hulls general theory of behavior
His theory explained the relationship between a
set of input variables and a set of output
variables by appealing to a set of intervening
variables with intervened between the input and
output variables.
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Examples

• Input variables
• Number of reinforcements (N)
• Drive condition (CD)
• Amount or quality of reward (w)
• Output variables
• Reaction latency (str)
• Reaction amplitude (A)
• Number of nonreinforced responses to extinction
  (n)

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Examples

• First level Intervening variables
• Habit strength (sHr) function of number of
  reinforcements
• Drive (D) function of drive condition
• Incentive (K) function of amount/quality of
  reward
• Conditioned inhibition (sIr) function of
  nonreinforced responses

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Examples

• Second level intervening variables
• Reaction potential sEr sHr x D x K
• Third level intervening variables
• Net reaction potential (reaction potential minus
  inhibitory potential). Net reaction potential
  determines output variables

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Hull on motivation

• Drive motivation pushes organism toward goal
• Appetative drives based on deprivation (e.g.,
  hunger, thirst)
• Aversive drives result through application of a
  stimulus (pain)
• Incentive motivation pulls organism toward the
  goal, the attractiveness of a goal

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Hull on reinforcement
Things that bring about a reduction in drive are
reinforcing. His theory is frequently referred
to as a drive reduction theory.
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B. F. Skinner(1904 - 1990)
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A brief personal history

• Born in a small town in Pennsylvania
• Obtains a degree in English from Hamilton College
  in upstate N.Y.
• Spends a couple of years in N.Y. City trying to
  be a writer.
• Enters graduate school at Harvard, obtains Ph.D.
  in 1931.
• After doing research at Harvard for 5 years, he
  accepts a teaching position at U. of Minnesota.

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A brief personal history contd

• In 1945 he becomes chair of the department at U.
  of Indiana.
• In 1948 he joins the department at Harvard where
  he stays through the rest of his life.

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Skinner on theory
Skinner argued that theory was not necessary and
that it was better to operate on the level of
empirical laws.
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Skinner on internal states
Skinner didnt deny the existence of internal
states (i.e., thoughts, emotions etc.), rather
her argued that they werent knowable by
objective science. Besides that, one didnt need
them to be able to explain behavior.
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Factors that shape behavior

• biology
• learning
• culture

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Types of conditioning

• Respondent conditioning (type S)
• Operant conditioning (type R)

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Skinners operant conditioning

• The operant chamber (aka the Skinner box)
• The cumulative recorder and the cumulative record
• Shaping
• Schedules of reinforcement
• Stimulus control

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Skinner on Freewill
Freewill is an illusion. Operant behavior is
governed by its past consequences.
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Skinner on verbal behavior
In his book Verbal Behavior (1957), Skinner
argues that operant conditioning can explain
human language. The book is severely criticized
by Noam Chomsky in a review that some say marks
the end of the behaviorist era.
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Skinners utopia
In 1948 Skinner published the novel Walden Two.
In it, he describes a commune in which behavioral
techniques have been used to shape happy and
industrious behaviors.
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Skinner and teaching machines
During the 1950s, Skinner developed the notion of
teaching machines. The teaching machine
required students to actively respond to
questions, after which they were given feedback
concerning the accuracy of their response. This
permitted individualized instruction on a large
scale