Transcript Learning

Learning
Learning is not attained by chance;
it must be sought for with ardor and
attended to with diligence.
Abigail Adams
Learning
Relatively permanent change in knowledge
or behavior resulting from experience
4 types of learning
Habituation
 Classical conditioning
 Operant conditioning
 Observational learning
 They all operate under the same principle –
learning by association

Habituation
Tendency to become familiar with a stimulus
merely as a result of repeated exposure
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Orienting reflex
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Eyes widen, eyebrows rise, muscles tighten, heart
beats faster, brain-waves indicate heightened
physiological arousal
Effect weakens with continued presentation of stimulus
– we habituate
Primitive form of learning

Found in all organisms
Decreases the power of reward to motivate
L E A R N IN G :
A r e la t i v e l y p e r m a n e n t c h a n g e i n b e h a v i o r t h a t r e s u lt s f r o m
e x p e rie n c e
PRINCIPLES
1 . L e a rn in g is a c h a n g e in m e n ta l s ta te . C h a n g e o c c u rs
i n s i d e t h e le a r n e r
2 . S e e n o n ly th ro u g h o b s e rv a tio n
3 . L e a r n i n g i n v o lv e s a c h a n g e o f b e h a v i o r
4 . R e s u lt s f r o m e x p e r i e n c e ( r e p e t i t io n )
5 . L e a r n i n g i s r e la t i v e l y p e r m a n e n t
6 . C a n b e a p p li e d / tr a n s f e r r e d t o a n e w s i t u a t io n
7 . W a t c h i n g , L i s t e n i n g , R e a d i n g , e t c . a l l c o n t r i b u t e to
le a r n i n g
LEARNING is based on an association between stimuli and responses
Classical Conditioning (Ivan Pavlov)
Stimulus elicits a Response [S  R]
EXAMPLE:
Bell rings, students leave!
I v a n P a v lo v
(R u s s ia n B io lo g is t)
D ig e stiv e s y ste m o f d o g s – sa liv a tio n a t th e sig h t o f fo o d is
e x p e c te d
C a n w e g e t th e d o g to s a liv a te a t th e a n tic ip a tio n o f f o o d ? ? ? ?
C a n w e g e t th e d o g to r e s p o n d to a n in a p p r o p ria te s tim u lu s ? ? ? ?
P a v lo v ’s d is c o v e r y le a d s to C la s s ic a l C o n d itio n in g
T h e E le m e n ts :
 U n C o n d itio n e d S tim u lu s (U C S )
 U n C o n d itio n e d R e sp o n se (U C R )
 N e u t r a l S t im u l u s ( N S )
 C o n d i t i o n e d S t im u l u s ( C S )
 C o n d itio n e d R e sp o n se (C R )
THE FORMULA
UCS  UCR
NS + UCS  UCR
CS  CR
IN OTHER WORDS
An unconditioned stimulus
elicits an unconditioned
response
A neutral stimulus paired
with an unconditioned
stimulus elicits an
unconditioned response
A conditioned stimulus
elicits a conditioned
response
Loud
Noise
_____
→
UCS
Balloon
_____
+
NS
Startle
_____
UCR
Loud
Noise
_____
→
UCS
Balloon
_____
CS
→
Startle
_____
UCR
Startle
_____
CR
Classical Conditioning
A tendency to connect events that occur
together in time and space
Pavlov (1849-1936)
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
Psychic secretions led to classical conditioning,
though unintentionally
A stimulus comes to elicit a response that it doesn’t
normally elicit
How does this come about?
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Unconditioned stimulus (UCS)
Unconditioned response (UCR)
Conditioned stimulus (CS)
Conditioned response (CR)
Basic Principles of Classical Conditioning
Acquisition
It takes some number of paired trials for the
learning (or acquisition) of a CR
 Key factors: order and timing of presentation

Extinction

The elimination of a learned response by
removal of the US or reinforcement
Stimulus Generalization

The tendency to respond to a stimulus that is
similar to the CS
Stimulus generalization
I don’t care if
she is a tape
dispenser.
I love her!
Basic Principles of Classical Conditioning
Acquisition


It takes some number of paired trials for the
learning (or acquisition) of a CR
Key factors: order and timing of presentation
Extinction

The elimination of a learned response by removal of
the US or reinforcement
Generalization

The tendency to respond to a stimulus that is similar
to the CS
Discrimination

The ability to distinguish between different stimuli
1. Acquisition
The process of developing a learned
response
2. Extinction
• The diminishing of a learned response
• Continuously presenting the CS without
the UCS
3. Generalization
• Producing the same response to two
similar stimuli
• The more similar the substitute stimulus
is to the original used in conditioning,
the stronger the generalized response
• Example: Little Albert
4. Discrimination
• Producing different responses to two
similar stimuli
Little Albert – Before Conditioning
Little Albert – During Conditioning
Little Albert – After Conditioning
Little Albert - Generalization
Things to keep in mind…
Classical – associate 2 things, thus
anticipate events

Lightening . . . . Thunder!
Unconditioned means unlearned

Associations should be natural
Response can be the same, but isn’t always
Contingency – CS should precede UCS
Simultaneous pairing takes longer and isn’t as
powerful
 Backwards pairing rarely works

Things to keep in mind…
Single-trial (or minimal-trial) learning

Phobias
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Little Albert
Taste aversions
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Cancer patients & chemotherapy
Applying Classical Conditioning
Conditioned Fears
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We have preferences for some fears
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They are learned more quickly and the associations last
longer, even during the extinction phase
Social Behaviors

People form strong positive and negative attitudes
toward neutral objects by virtue of their links to
emotionally charged stimuli
Immune System

Preliminary research shows that we can slow/bolster
the immune system through classical conditioning
Operant Conditioning
Operant conditioning
Associate response with its consequence
 Behavior becomes more or less probable
depending on its consequences

Law of effect

Responses followed by positive outcomes are
repeated whereas those followed by negative
outcomes are not
Operant Conditioning
Skinner boxes
Behavioral contingencies
Positive reinforcement
 Negative reinforcement
 Extinction
 Punishment
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Reinforcement
Reinforcer

A consequence that increases the likelihood that
behavior will occur again
Positive reinforcement
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Providing a positive stimulus
Studying earns you a good grade
Premack principle

More probable behavior can be used as a reinforcer for
less probable behavior
Negative reinforcement
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Removing an aversive stimulus
Fastening our seatbelts to turn of the buzzer
Punishment
Punishment

A consequence that decreases the likelihood
that behavior will occur again
Positive punisher
Providing an aversive stimulus
 Scolding a child, shocking a lab rat for
pressing the response lever

Negative punisher
Removing a positive stimulus
 Taking food away from a hungry rat
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Shaping and Extinction
Shaping
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Encouraging a new behavior by reinforcing successive
approximations
This is how trainers get animals to do new tricks
Extinction
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As in classical conditioning, failure to reward the
learned behavior will eventually lead to a cessation of
that behavior
If a vending machine stops giving you a Coke, you’ll
stop putting your money into it
Things to keep in mind . . .
Primary vs. secondary reinforcers
Primary – stimuli that are innately reinforcing
 Secondary – stimuli that are rewarding
because of their association with primary
reinforcers

Why don’t the behaviors
just keep occurring?
Discriminative stimulus
 Relative degree of satiation

Reinforcement Schedules
Continuous
Learning occurs rapidly
 Subject to rapid extinction when discontinued

Partial
Fixed-Interval (FI)
 Variable-Interval (VI)
 Fixed-Ratio (FR)
 Variable-Ratio (VR)
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Behavioral Contingencies
Type
Consequence
Prob. of
behavior
Example
Positive
reinforce
Add
desirable
Increase
Study and
get an “A”
Negative
reinforce
Remove
undesirable
Increase
Go to dentist;
filling removes
pain
Extinction
Fail to add
desirable
Decrease
Say hi. No
response. Stop
saying hi
Decrease
Hangover
Decrease
Get benched
for fighting
“Positive”
Add
Punishment undesirable
Remove
“Negative”
Punishment desirable
Observational Learning
Not all learning comes from direct
experience!
Sometimes we watch others & see what
happens…
Older siblings, peers, & parents
 Vicarious rewards & punishments
 Also: intrinsic rewards & punishments

Albert Bandura
Bobo doll studies
2 stages of observational learning
Acquisition
 Performance
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4 steps of observational learning
Attention
 Retention
 Reproduction
 Motivation
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