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Chapter 7: Learning
LEARNING: a relatively permanent change in an organism's behavior due to experience.
We learn by association
Our minds naturally connect events that occur in sequence
ASSOCIATIVE LEARNING: learning that two events occur together
Both classical and operant conditioning are forms of associative learning
Classical or Pavlovian Conditioning
We learn to associate two stimuli—then to anticipate events
Operant Conditioning
We learn to associate a response and its consequence
Classical Conditioning
Ivan Pavlov---Russian physician/ neurophysiologist
Pavlov’s Classic Experiment—dogs and salivation
Classical Conditioning---kind of learning in which a previously neutral stimulus comes to
elicit a response through its association with a stimulus that naturally brings about the
response
Neutral Stimulus: before conditioning, a stimulus that the does not naturally bring about a
response. Dogs—light or tone
Unconditioned Stimulus:
UCS stimulus that naturally and automatically brings about a
response, without having been learned. Smell of food
Unconditioned Response: UCR unlearned, natural response to the unconditioned stimulus.
(needs no training )e.g. salivation at the smell of food Involuntary response or reaction
Conditioned Stimulus: CS a once neutral stimulus that comes to elicit a CR after it has
been paired with an unconditional stimulus. The event that takes on new meaning through
conditioning. Dogs—light or tone
For the most rapid conditioning, a CS should be presented: about one-half-second before the
US
Conditioned Response: CR learned response to a previously neutral conditioned stimulus
The new behavior that is acquired through learning. Salivation at sight of light
Acquisition--initial stage in classical conditioning. Where organisim associates a neutral
stimulus with an unconditioned stimulus so that the neutral stimulus comes to elicit a
conditioned response
strengthening of a reinforced response
Extinction--diminishing of a CR
in classical conditioning, when a UCS does not follow a CS
in operant conditioning, when a response is no longer reinforced
Spontaneous Recovery
reappearance, after a rest period, of an extinguished CR
In Pavlov's studies of a dog's salivary responses, spontaneous recovery occurred when the CS
was reintroduced following extinction of the CR and a rest period
Generalization
tendency for stimuli similar to CS to elicit similar responses
Discrimination
in classical conditioning, the learned ability to distinguish between a CS and other stimuli
that do not signal a UCS
Cognitive processes
Pavlov legacy
Applications of classical conditioning
Classical conditioning may play a role in
Emotional problems
The body’s immune response
Helping drug addicts
OPERANT CONDITIONING - also called instrumental conditioning
based on the consequences of an organism’s behavior.
Behavior is strengthened if followed by reinforcement and diminished if followed by
punishment.
Edward Thorndike---later B. F. Skinner-- occurs when people or animals learn by the
consequences of their responses. Consequences consist of reinforcement or punishment.
Law of Effect
Thorndike’s principle ---behaviors followed by favorable consequences become more
likely, and behaviors followed by unfavorable consequences become less likely
Responses that are satisfying are more likely to be repeated, and those that are not satisfying
are less likely to be repeated
Operant Behavior
operates (acts) on environment; produces consequences
Respondent Behavior
occurs as an automatic response to stimulus
B.F. Skinner elaborated Thorndike’s Law of Effect
Operant Chamber
Skinner Box
chamber with a bar or key that an animal manipulates to obtain a food or water reinforcer
contains devices to record responses
Shaping
operant conditioning procedure in which reinforcers guide behavior toward closer
approximations of a desired goal
Principles of Reinforcement
Reinforcer: any event that strengthens the behavior it follows
Reinforcement is anything that is likely to cause and increase in the response.
Positive reinforcement occurs when something is added to increase the response rates.
Negative reinforcement--occurs when something is removed in order to increase the response
rate.
different from punishment
Punishment is anything that is likely to cause a decrease in the response.
Primary Reinforcer innately reinforcing stimulus, i.e., satisfies a biological need
(food, water, sex)
Conditioned Reinforcer or secondary reinforcer: reinforcers that acquire positive value
through experiences (money, smiles, grades)
Conditioned or Learned reinforcers gain power through its association with primary
reinforcer
Primary reinforcers satisfy an unlearned biological need and secondary reinforcers have
learned value.
Example of reinforcements:
Presenting a positive stimulus after a response
Removing an unpleasant stimulus after a response
Being told you have done a good job
Immediate & Delayed Reinforcers
Immediate Reinforcer: A reinforcer that occurs instantly after a behavior. A rat gets a food
pellet for a bar press.
Delayed Reinforcer: A reinforcer that is delayed in time for a certain behavior. A paycheck
that comes at the end of a week.
Two kinds of punishment
Positive punishment occurs when something is given to decrease the response rate.
Negative punishment consists of removing something to decrease the response rate. (think in
mathematical terms – positive (add) and negative (take away).
Disadvantages to using punishment:
Often ineffective—if not delivered right away
Use of physical punishment: teach that aggression is OK
Begin to fear the “punisher”
Physical punishment given by angry person who may be more likely to lose control
Reduces self esteem of recipient
Does not convey info about what is appropriate behavior
To be effective: Needs to be accompanied by specific info about behavior being punished;
along with specific suggestions concerning more desirable behaviors
Operant response rates remain highest when individuals anticipate that their behavior will
actually lead to further reinforcement, illustrating the importance of cognitive processes in
operant conditioning.
Cognitive Map
mental representation of environment; the layout of one’s environment
Example : After discovering that her usual route home was closed due to road repairs,
Sharetta used her knowledge of the city and sense of direction to find an alternate route.
Latent Learning
learning that occurs, but is not apparent until there is an incentive to demonstrate it
Learning in which a new behavior is acquired but not demonstrated until reinforcement is
provided
The fact that learning can occur without reinforcement is most clearly demonstrated by
studies of: latent learning
Cognitive-Social learning theory: The study of the thought processes that underlie learning
Observational Learning
Learning by observing and imitating others' behaviors , through observing the behavior of
another person called a model
Alfred Bandura we look and we learn
Bobo doll: This experiment served to illustrate the importance of observational learning--preschool children pounded and kicked a large inflated Bobo doll that an adult had just beaten
on.
Modeling: process of observing and imitating a specific behavior
model: A person serving as an example to an observer; if a model’s behavior is rewarded, the
observer may imitate that behavior
After watching coverage of the Olympics on television recently, Lynn and Susan have been
staging their own “winter games”
Most likely to imitate the behavior of models if observe that their actions are followed by
reinforcement
In promoting observational learning, the most effective models are those that we perceive as
similar to ourselves
respected and admired
successful
Prosocial Behavior
positive, constructive, helpful behavior
opposite of antisocial behavior
Television and Observational Learning: does watching TV have any effect on behavior?