Ch. 6: William James

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Chapter 9: Behaviourism
A History of Psychology
(3rd Edition)
John G. Benjafield
Ivan P. Pavlov (1849–1936)
• Set out to become a priest
– Abandoned idea after reading a Russian
translation of Darwin
• 1883: became a medical doctor
• 1904: awarded Nobel Prize
– Work on the physiology of the digestive
system
Pavlov’s Animals
• Early career:
– Often took his animals home because of a
lack of facilities at the university
• Later career:
– Constructed an Institute of Experimental
Medicine in St Petersburg (1891)
Conditioned Reflexes
• I.M. Sechenov (1829–1905): Cerebral
Reflexes
– Proposed that mental life should be
understood entirely in physiological terms
– Reflex is the appropriate unit of explanation
• Pavlov dissociated himself from the
psychology of the time
Conditioned Reflexes
•
Unconditioned reflexes
– The same response always occurs in the
presence of the same stimulus
•
•
•
•
Unconditioned Stimulus
Conditioned Stimulus
Conditioned Response
Unconditioned Response
Facts: Conditioning
•
•
•
A conditioned response is usually smaller
in magnitude than an unconditioned one
Extinction: The CR will eventually cease
if the CS is repeatedly presented alone
Spontaneous recovery: A previously
extinguished CR may return after a
period of rest
Speech
• Higher-order conditioning: A second CS is
paired with a CS that has already been
established
• Primary signalling system: consists largely
of sensory stimuli
• Secondary signalling system: consists
largely of words
– Words name primary signals
Temperaments and
Psychopathology
• Fundamental cortical processes:
– Excitation
– Inhibition
• Temperaments arranged on a scale:
– Choleric (extremely excitatory)
– Sanguine
– Phlegmatic
– Melancholic (extremely inhibitory)
Vivisection and Anti-vivisectionism
• Vivisection: the dissection of live animals
• Anti-vivisectionism: the movement against
the use of live animals in research
Vladimir M. Bekhterev (1857–1927)
• Reflexology: attempt to explain all
behaviour, from the individual to the social,
in terms of the reflex concept
• Developed a technique for studying
associated motor reflexes in both dogs
and humans
John B. Watson (1878–1958)
• 1899: graduated from Furman University
• Graduate student at University of Chicago
– Impressed by Jacques Loeb (1859–1924)
– 1903: doctoral dissertation in animal
psychology
• 1908: Faculty at Johns Hopkins University
‘Psychology as the Behaviourist
Views It’
• Published in 1913
• Challenged psychologists to change
virtually every aspect of their discipline:
– Not a study of consciousness
– Study human behaviour in same way as
animal behaviour
Habits
• Behaviorism (1939): humans are unique
because of the variety of habits they can
form through conditioning
1. Visceral (emotional) habits
2. Manual habits
3. Laryngeal (verbal) habits
Emotional Habits
• Can only study emotion via very young
children
• Innate emotional responses: fear, rage,
love
• Little Albert study
– Produced conditioned emotional reactions in
an 11-month-old infant
Manual Habits
= the entire range of muscular responses
• Manual habits form through repetition
– Formation permits smooth transition from one
situation to the next
• Watson advocated distributed practice to
acquire skills (vs. massed practice)
Verbal Habits
• Thought same as internal speech
• Verbal habits constitute thinking
• Speech is a serially-ordered behaviour
Watson’s Second Career
• Following second marriage (to Rosalie
Rayner), Watson worked for:
– J. Walter Thompson advertising agency
– William Esty & Co.
• Watson transferred principles of
conditioning to advertising
Karl S. Lashley (1890–1958)
• Undergraduate at University of West
Virginia
• PhD at Johns Hopkins
– Under Herbert S. Jenings
• Postdoctoral studies with Watson
Cortical Localization of Function
• 1916: Lashley studied with Shepherd Ivory
Franz
– Ablation: technique by which parts of the
cortex are destroyed and the results observed
– Studied the effects of ablation on the frontal
lobes in rats
• 1917: moved to University of Minnesota
Brain Mechanisms and Intelligence
• Law of mass action: learning and memory
depend on the total mass of brain tissue
remaining
• Law of equipotentiality: within limits, any
part of an area can do the job of any other
part of that area
The Problem of Serial Order in
Behaviour
• Criticized Watson’s associative chain
theory
– Priming of responses
– Spoonerisms
B.F. Skinner (1904–1990)
• ‘. . . behaviour which seemed to be the
product of mental activiy could be
explained in other ways.’
• Consciousness = a form of behaviour
The Behavior of Organisms
• Published in 1938
• Respondent behaviour: elicited by a
known stimulus
• Operant behaviour: no known eliciting
stimulus
– Studied by means of a Skinner box
The Behavior of Organisms
• Behaviour regulated by Three-term
Contingencies:
– Environment provides a stimulus situation
– Which elicits a response
– Which is followed by a reinforcing stimulus
• Reward or punishment
–Negative reinforcement ≠ punishment
A Case History in Scientific Method
• Published in 1956
• Discussed the ways in which Skinner
made discoveries
– Applied the principles of his psychology to his
own creativity
• Ex. ‘When you run into something
interesting, drop everything else and study
it’
• Ex. ‘Apparatuses sometimes break down’
The ‘Baby Tender’
• Air crib = ‘Baby tender’
• Built for his second daughter
• Wrote about the innovation in the popular
press
– ‘Baby in a box’
Teaching Machines
• Typical classroom: reinforcement only
when the child does the work required to
avoid punishment
• Skinner suggested: reinforce students for
each response in a sequence that
gradually builds up
Skinner’s Utopian and
Dystopian Views
• Walden Two (1948)
– Utopian novel of a community regulated by
positive reinforcement
– Received mixed reviews
• Skinner increasingly discussed the
dystopian features of modern life in the
West
– Dystopia: a society that is the opposite of a
Utopia
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