3. Adaptation to the Environment
• Learning—any process
through which experience at
one time can alter an
individual’s behavior at a
future time
4. Adaptation to the Environment
• Conditioning—the process of
learning the associations
between environmental
events and behavioral
responses
5. Behaviorism
• The attempt to understand
observable activity in terms
of observable stimuli and
observable responses
• John B. Watson (1913)
• B. F. Skinner (1938)
10. Unconditioned Response—
Salivation
• A response to an
unconditioned stimulus—
naturally occurring
–Salivation at smell of food
–Eye blinks at blast of air
–Startle reaction in babies
11. Conditioned Stimulus—Bell
• The stimulus that was originally
neutral becomes conditioned after
it has been paired with the
unconditioned stimulus
• Will eventually elicit the
unconditioned response by itself
12. Conditioned Response
• The original unconditioned
response becomes conditioned
after it has been elicited by the
neutral stimulus
15. John B. Watson and Little Albert
• Conditioned
emotional
responses
• Generalization
• Extinction
16.
17.
18. Classical Conditioning and Drug Use
• Regular use may produce “placebo
response” where user associates sight,
smell, taste with the drug effect
• Conditioned compensatory response (CCR)
—classically conditioned response in which
stimuli that reliably precede the
administration of a drug elicit physiological
reaction that is opposite to the drug’s effects.
May be one explanation for the
characteristics of withdrawal and tolerance.
19. Cognitive Aspects of
Classical Conditioning
• Reliable and unreliable signals
• Actively process information
• Robert Rescorla
20. Evolutionary Perspective
• Conditioned taste aversions
• Internal stimuli—associate better with taste
• External stimuli—associate better with pain
• Biological preparedness
• John Garcia—not all neutral stimuli can
become conditioned stimuli.
21. Early Operant Conditioning
• E. L. Thorndike (1898)
• Puzzle boxes and cats
Scratch at bars
Push at ceiling
Dig at floor
Situation:
stimuli
inside of
puzzle box
Howl
Etc.
Etc.
Press lever
First Trial
in Box
Scratch at bars
Push at ceiling
Dig at floor
Situation:
stimuli
inside of
puzzle box
Howl
Etc.
Etc.
Press lever
After Many
Trials in Box
24. B. F. Skinner’s
Operant Conditioning
• Did not like Thorndike’s term
“satisfying state of affairs”
• Interested in emitted behaviors
• Operant—voluntary response
that acts on the environment to
produce consequences
25. Reinforcement—the occurrence
of a stimulus following a
response that increases the
likelihood of the response being
repeated
Operant Conditioning
26.
27. Reinforcers
• Primary—a stimulus that is inherently
reinforcing for a species (biological
necessities)
• Conditioned—a stimulus that has acquired
reinforcing value by being associated with
a primary reinforcer
28. Punishment
Presentation of a stimulus following
a behavior that acts to decrease
the likelihood that the behavior will
be repeated
29. Problems with Punishment
• Does not teach or promote
alternative, acceptable behavior
• May produce undesirable results
such as hostility, passivity, fear
• Likely to be temporary
• May model aggression
33. Reinforcement Schedules
• Continuous—every correct response
is reinforced; good way to get a low-
frequency behavior to occur
• Partial—only some correct responses
are reinforced; good way to make a
behavior resistant to extinction
34. Partial Schedules—Ratio
• Ratio schedules are based on
number of responses emitted
• Fixed ratio (FR)—a reinforcer is
delivered after a certain (fixed)
number of correct responses
• Variable ratio (VR)—a reinforcer is
delivered after an average number of
responses, but varies from trial to trial
35.
36. Partial Schedules—Interval
• Interval schedules are based on time.
• Fixed interval (FI)—reinforcer is delivered
for the first response after a fixed period of
time has elapsed
• Variable interval (VI)—reinforcer is
delivered for the first response after an
average time has elapsed, differs between
trials
37. Cognitive Aspects of
Operant Conditioning
• Cognitive map—term for a mental
representation of the layout of a familiar
environment
• Latent learning—learning that occurs in
the absence of reinforcement, but is not
demonstrated until a reinforcer is available
• Learned helplessness—phenomenon in
which exposure to inescapable and
uncontrollable aversive events produces
passive behavior
42. Do as I say, not as I do.
This will teach you to hit your
brother!
Why do you do that? You know
you get in trouble for it.
Famous Last Words???
Hinweis der Redaktion
Extinction- lack of reinforcement of the response and the resulting decline in response rate -an operantly conditioned response declines in rate and eventually disappears if it no longer results in a reinforcer ex: rats quit pressing levers if food pellets no longer appear Extinction is not true “unlearning” of the response but rather a learned inhibition of responding The mere passage of time following extinction can partially renew the conditioned reflex; called spontaneous recovery Generalization- phenomenon in which , after conditioning, stimuli that resemble the conditioned stimulus will elicit the conditioned response even though they themselves were never paired with the unconditioned response. Discrimination training can abolish generalization between two stimuli. By not linking the unconditioned stimulus to the neutral stimulus that has been generalized to, the animal will discriminate.
Thorndike put cats into puzzle boxes and made them find the solution to their quandary. Thorndike did not elicit a response as Pavlov had, he had to wait for the animal to emit the proper response, learn from it and do it again. The trial and error process through which the animals learned the way to trip the latch was what Thorndike called his law of effect. Responses that produce a satisfying effect in a particular situation become more likely to occur again in that situation, and responses that produce a discomforting effect become less likely to occur again in that situation. Instrumental responses - actions which function as tools to work some change in the environment; also called operant responses. Ex: flipping a switch to light a room; rats pushing a lever to receive food Operant conditioning- learning process by which the consequence of an operant response affects the likelihood that the response will occur in the future.
We are pulled as well as pushed by events in our environment. We do not just react to stimuli; we also behave in ways to produce or obtain certain environmental changes or stimuli. Shaping- process in which successively closer approximations to the desired response are reinforced until the response finally occurs Consequences- what happens after a response positive reinforcement - the arrival of some stimulus following a response which makes the response more likely to occur; stimulus called a positive reinforcer negative reinforcement- the removal of some stimulus following a response which makes the response more likely to occur; stimulus called a negative reinforcer punishment- opposite of reinforcement; the consequence of a response decreases the likelihood that the response will occur
