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Chapter 6
LEARNING
Learning
• Learning –
A process through which experience
produces lasting change in behavior or
mental processes.
Behavioral Learning vs. Cognitive Learning
Simple Forms of Learning
• Habituation –
Learning not to respond to repeated
presentation of a stimulus.
• Mere exposure effect –
Learned preference for stimuli to
which we have been previously exposed.
What Sort of Learning Does
Classical Conditioning Explain?
Classical conditioning is a
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.
CLASSICAL CONDITIONING
• The process by which an organism learns a
new association between two paired stimuli.
• Neutral stimulus –
any stimulus that
produces no response.
» IVAN PAVLOV
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
The stimulus that elicits
an unconditioned
response.
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
The response elicited
by an unconditioned
stimulus without prior
learning.
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
A previously neutral
stimulus that comes to
elicit the conditioned
response.
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
A response elicited by a
previously neutral
stimulus that has
become associated with
the unconditioned
stimulus.
Classical Conditioning
• Acquisition – the
process by which
a conditioned
response is
established or
strengthened.
• Extinction – the
weakening of a
CR in the
absence of an
UCS.
Classical Conditioning
• Spontaneous Recovery – the
reappearance of an extinguished
conditioned response after a time delay.
(1)
Acquisition
(CS + UCS)
(2)
Extinction
(CS alone)
(Time)
Trials
Rest period
Strength of the CR
(Weak)
(Strong)
Acquisition, Extinction, and
Spontaneous Recovery
(3)
Spontaneous
Recovery
(CS alone)
Classical Conditioning
• Generalization – the
extension of a CR
from the training
stimulus to similar
stimuli.
• Discrimination –
making different
responses to different
stimuli that have been
followed by different
outcomes.
Classical Conditioning
• Taste-aversion learning – a biological
tendency in which an organism learns,
after a single experience, to avoid a food,
if eating 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.
Operant Conditioning
• The probability of a
response is changed by
its consequences.
• Law of Effect –
– Responses that produce
desirable results will be
learned.
Operant Conditioning
Reinforcement:
The process in which a
behavior is strengthened,
and thus, more likely to
happen again.
Punishment
The process in which a
behavior is weakened,
and thus, less likely to
happen again.
Operant Conditioning
+ Positive Reinforcement
Making a behavior
stronger by following the
behavior with a pleasant
stimulus.
Example: a rat presses a
lever and receives food.
- Negative Reinforcement
Making a behavior
stronger by taking away
a negative stimulus.
Example: a rat presses a
lever and turns off the
electric shock.
PUNISHMENT
+ Positive punishment
– The application of an aversive stimulus after
a response.
Example: You touch a hot plate; the painful
consequence reduces the likelihood of you repeating
that behavior.
- Negative punishment (omission training)
- Results from the removal of a reinforcer.
Example: Your parents take away your cell phone
because you are not doing well in school.
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 (learned helplessness)
– Is often applied unequally
•
When does punishment work?
Primary vs Secondary Reinforcers
• Primary
– Innate (unlearned)
• Secondary
– Conditioned (learned)
Shaping
• A technique in which a new behavior is
produced by reinforcing responses that
are similar to the desired response.
Token Economy
• Conditioning in which desirable behavior is
reinforced with tokens, which can be
accumulated and exchanged for valued
rewards.
Premack Principle
• More preferred activities can be used to
reinforce less preferred activities.
"You have to finish your VEGETABLES
(Low Frequency) before you can eat any
ICECREAM (High Frequency)."
Behavior Modification
• Replaces undesirable
behaviors with more
desirable ones
through positive or
negative
reinforcement.
*Positive reinforcement
seems to be the most
effective technique.
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.
– called intermittent reinforcement
Schedules of Reinforcement
• Ratio schedules –
Provide reward after a certain number of
responses.
• Interval schedules –
Provide reward after a certain time
interval.
Fixed Ratio (FR)
Variable Ratio (VR)
Fixed Interval (FI)
Variable Interval (VI)
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after
a certain set number
of responses.
e.g. factory workers
getting paid after
every 10 cases of
product are completed
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after
a certain number of
responses, but that
number varies from
trial to trial.
e.g. slot machine payoffs
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after
a certain fixed amount
of time, regardless of
number of responses.
e.g. weekly or monthly
paychecks
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after a
certain amount of time,
but that amount varies
from trial to trial.
e.g. random visits from
the boss who delivers
praise
Classical vs. Operant Conditioning
• Classical Conditioning
– involves the
association of two
stimuli (UCS + CS)
before the response
or behavior.
• Operant Conditioning
– involves a
reinforcing
(reward) or
punishing stimulus
after a response or
behavior.
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.
Cognitive Psychology
• Insight learning –
Problem solving occurs by means
of a sudden reorganization of
perceptions. - Kohler
• Cognitive map –
A mental representation of physical
space. - Tolman
Observational Learning
• Form of cognitive learning in which new
responses are acquired after watching
others’ behavior and the consequences of
their behavior.
• Bandura
– BoBo doll experiment
Violence in the Media
• Observing violence
is associated with
violent 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.
In Summary…
• Behavioral Learning
– Focuses on observable
events.
– Learning as
associations among
stimuli and responses.
– Classical and operant
conditioning.
Big Names:
•
•
•
•
Pavlov
Thorndike
Skinner
Watson
• Cognitive Learning
– Makes inferences about
mental processes that
are not directly
observable.
– Learning as information
processing.
– Learning involves insight
and cognitive maps.
Big Names:
• Kohler
• Tolman
• Bandura