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Chapter 6
Learning
Learning
Learning –
A process through
which experience
produces lasting
change in behavior or
mental processes
Habituation –
Learning not to
respond to repeated
presentation of a
stimulus
Learning – Can be Simple or Complex
Mere exposure effect –
Learned preference for stimuli to which
we have been previously exposed
Behavioral learning –
Forms of learning that can be described
in terms of stimuli and responses
(e.g. classical and operant conditioning)
What Sort of Learning Does
Classical Conditioning Explain?
Classical conditioning is a
basic form of learning in which
a stimulus that produces an
innate reflex becomes
associated with a previously
neutral stimulus, which then
acquires the power to elicit
essentially the same response
The Essentials of Classical
Conditioning
Neutral stimulus –
Any stimulus that produces
no conditioned response
prior to learning
Acquisition –
Initial learning stage in
classical conditioning;
conditioned response
becomes elicited by the
conditioned stimulus
Essentials of Classical Conditioning
Prior to conditioning
Neutral stimulus
(bell)
(Orientation to sound
but no response)
Unconditioned stimulus
(meat)
Unconditioned response
(salivation)
During Conditioning
Neutral stimulus
(bell)
+
Unconditioned stimulus
(meat)
Unconditioned response
(salivation)
After conditioning
Conditioned stimulus
(bell)
Conditioned response
(salivation)
Think of it as a formula!
Before Conditioning:
(UCS) meat = (UCR) salivation
During Conditioning:
(NS) bell + (UCS) meat = (UCR) salivation
After Conditioning:
(CS)
bell
=
(CR) salivation
Classical Conditioning
Extinction –
Weakening of a conditioned association
in the absence of an unconditioned
stimulus or reinforcer
Spontaneous recovery –
Reappearance of an extinguished
conditioned response after a time delay
Classical Conditioning:
Generalization and Discrimination
Stimulus generalization
involves giving a conditioned
response to stimuli that are
similar to the CS
Stimulus discrimination
involves responding to one
stimulus but
not to stimuli that are similar
Confusing stimuli may cause
experimental neurosis
Applications of Classical Conditioning
Taste-aversion learning –
Biological tendency in which an organism
learns to avoid food with a certain taste
after a single experience, if eating it is
followed by illness
How Do We Learn
New Behaviors by
Operant Conditioning?
In operant conditioning, the
consequences of behavior,
such as rewards and
punishments, influence the
chance that our behavior will
occur again
How Do We Learn
New Behaviors by
Operant Conditioning?
Trial-and-error learning –
Learner gradually discovers the correct
response by attempting many behaviors
and noting which ones produce the
desired consequences
Skinner’s Radical Behaviorism
B.F. Skinner believed that the most
powerful influences on behavior are its
consequences
Consequences are Powerful!
Reinforcement
• Strengthens
• Increases
• Encourages
the likelihood that a behavior will
happen again.
The Power of Reinforcement
Positive (added) Reinforcement –
An appetitive (liked) stimulus is added after a
response/behavior which increases the
probability of that response/behavior happening
again.
Negative (removed) Reinforcement –
A response/behavior occurs in order to remove
an aversive (disliked) stimulus, which increases
the probability of that response/behavior
happening again.
Consequences are Powerful!
Punishment
• Weakens
• Decreases
• Discourages
the likelihood that a behavior will
happen again.
The Power of Punishment
Positive punishment –
The application of an aversive
(disliked) stimulus after a
response/behavior, which
decreases the
response/behavior from
happening again.
Omission training (negative
punishment) –
The removal of an appetitive
(liked) stimulus after a
response/behavior, which
decreases the
response/behavior from
happening again.
Four Kinds of Consequences
STIMULUS
+
Present
Appetitive
(like)
Aversive
(dislike)
Positive
Reinforcement
Positive Punishment
$ Bonus for working
hard
leads to more hard work
Omission Training
Remove
Having your cell phone
taken away for coming
home late
Getting speeding ticket
leads to less speeding
Negative
Reinforcement
Taking an aspirin to
remove headache causes
more aspirin use.
Copyright © Allyn & Bacon 2007
So, is it Negative Reinforcement or
Punishment?
Negative
Reinforcement
(Aversive
Stimulus)Threat of
being grounded
Response
Consequence
Come home
on time
Not grounded
Punishment
No Stimulus
Stayed out
Late
Grounded
Copyright © Allyn & Bacon 2007
The Use and Abuse of Punishment
Power usually disappears when threat of
punishment is removed
Punishment
•
•
•
Often triggers aggression
May inhibit learning new and better
responses
Is often applied unequally
When does punishment work?
Alternatives to Punishment
Extinction
Reinforcing preferred activities
Premack principle
Prompting and shaping
Other Types of Reinforcement
Primary reinforcers –
Reinforcers, such as food and sex, that
have an innate basis because of their
biological value to an organism
Other Types of Reinforcement
Secondary reinforcers –
Stimuli, such as money or tokens, that
acquire their reinforcing power by their
learned association with primary
reinforcers
(also called conditioned reinforcers)
Contingencies of Reinforcement
Continuous reinforcement –
Reinforcement schedule in which all
correct responses are reinforced
Partial reinforcement –
Reinforcement schedule in which some,
but not all, correct responses are
reinforced
(also called intermittent reinforcement)
Contingencies of Reinforcement
Extinction –
In operant conditioning, a process by
which a response that has been learned
is weakened by the absence or removal
of reinforcement
How does this differ from extinction in
classical conditioning?
Schedules of
Reinforcement/Punishment
Ratio schedules :
(Ratio = Behavior) (Root Beer)
Provide reinforcement/punishment after a certain
number/repetition of responses/behaviors occur. (Can’t
get the root beer out of the vending machine until you
put 4 quarters into the machine).
Interval schedules :
(Interval = Time) (Iced Tea)
Provide reinforcement/punishment after a certain time
interval lapses following the behavior/response. (It’s not
iced tea until the tea-bag steeps for 5 minutes).
Copyright © Allyn & Bacon 2007
Two Types of Schedules
Fixed:
Reinforcement is given in a set, predictable
pattern.
Variable:
Reinforcement is given in a varied,
unpredictable pattern.
Ratio Schedules
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Reinforcement/punishment
appears after a certain set
number of responses
e.g. Buy 1 get 1 free.
e.g. 3 strikes and
you’re out!
Variable Interval
(VI)
Copyright © Allyn & Bacon 2007
Ratio Schedules
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Reinforcement/Punishment
appears after a certain
number of responses, but
that number varies from trial
to trial
e.g. slot machine payoffs
e.g. Getting your cell
phone taken away at
school.
Copyright © Allyn & Bacon 2007
Interval Schedules
Variable Ratio
(VR)
Reinforcement/punishment
appears after a certain
fixed amount of time,
regardless of number of
responses
Fixed Interval
(FI)
e.g. weekly or monthly
paychecks
Fixed Ratio (FR)
Variable Interval
(VI)
e.g. report cards
Copyright © Allyn & Bacon 2007
Interval Schedules
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Reinforcement/punishment
appears after a certain
amount of time, but that
amount varies from trial to
trial
e.g. fishing
e.g. Tardy Sweeps;
Variable Interval Sobriety Check Points
(VI)
Copyright © Allyn & Bacon 2007
What is the reinforcement schedule?
1. Speed traps on the highway
2. Selling a product door to door
3. Getting the clothes from the dryer once it buzzes
4. Doing 20 pushups to stay fit
5. Playing Bingo
6. Getting a strike in bowling (if you’re not a pro!)
7. Surfer waiting for the perfect wave to ride in
8. Wife getting a kiss from her husband for every touchdown his
football team gets.
9. Husband getting a kiss from his wife at the beginning of every
commercial break while he watches Dancing with the Stars
with her.
Copyright © Allyn & Bacon 2007
How Does
Cognitive Psychology
Explain Learning?
According to cognitive
psychology, some forms of
learning must be explained
as changes in mental
processes, rather than as
changes in behavior alone
How Does
Cognitive Psychology
Explain Learning?
Insight learning –
Problem solving occurs by means of a
sudden reorganization of perceptions
How Does
Cognitive Psychology
Explain Learning?
• Cognitive maps –
A mental representation of physical
space
Observational Learning: Bandura’s
Challenge to Behaviorism
Observational learning –
Form of cognitive learning in which new
responses are acquired after watching
others’ behavior and the consequences
of their behavior
Brain Mechanisms and Learning
Long-term potentiation –
Biological process involving physical
changes that strengthen the synapses in
groups of nerve cells; believed to be the
neural basis of learning
Congratulations (Positive Reinforcement)! You made it to the
end of the chapter (Fixed Ratio). Your hard work will pay off
on the test on Wednesday (Fixed Interval). You will receive a
good grade (positive reinforcement), which will shape the future
behavior of studying (operant conditioning), and you will have
fond memories of feeling good every time you hear the word
“study” (classical conditioning). And, if you see other people
succeeding in class, that will prompt you to do your work and
study (observational learning). Now, go get yourself a treat for
working so hard (Premack principal).
End of Chapter 6