Transcript Learning

Learning
Long lasting change
in behavior due to
experience.
Classical Conditioning
• Ivan Pavlov
• Studied Digestion of
Dogs.
• Dogs would salivate
before they were
given food (triggered
by sounds, lights
etc…)
• Dogs must have
LEARNED to salivate.
Click above to see about Pavlov
Classical Conditioning
• This is passive learning
(automatic…learner does
NOT have to think).
• First thing you need is a
unconditional relationship.
• Unconditional Stimulus
(UCS)- something that
elicits a natural, reflexive
response.
• Unconditional Response
(UCR)- response to the
UCS.
Classical Conditioning
• Next you find a neutral stimulus (something
that by itself elicits no response).
• You present the stimulus with the UCS a
whole bunch of times.
Classical Conditioning
• After a while, the
body begins to link
together the neutral
stimulus with the
UCS.
• Acquisition
Classical Conditioning
• We know learning takes
places when the
previously neutral
stimulus elicits a
response.
• At this point the
neutral stimulus is
called the conditioned
stimulus (CS) and the
unconditional response
becomes the
conditioned response
(CR).
Classical Conditioning
• TRICKY FACT: We
know learning exists
because the CS is
linked to the UCS.
• This is called
ACQUISITION.
• Acquisition does not
last forever.
• The moment the CS is
no longer associated
with the UCS, we have
EXTINCTION.
Popular Classical Conditioning
Examples
See if you can identify the UCS, UCR, CS and CR.
Classical Conditioning as
portrayed in The Office.
A modified version of Clockwork
Orange scene. Warning…it is still
graphic!!!
Timing Matters
• Delayed Conditioning: present CS, while CS is still there,
present UCS.
• Trace Conditioning: present CS, short break, then
present UCS.
• Simultaneous Conditioning: CS and UCS are presented at
the same time.
• Backward Conditioning: UCS is presented, then CS is
presented.
Spontaneous Recovery
• Sometimes, after
extinction, the CR
still randomly
appears after the
CS is presented.
Generalization and Discrimination
Generalization
• Something is so similar
to the CS that you get a
CR.
Discrimination
• Something so different
to the CS so you do not
get a CR.
Classical Conditioning and Humans
• John Watson brought Classical Conditioning to
psychology with his Baby Albert experiment.
Click to
see Baby
Albert to
some nice
jazz.
This type of Classical Conditioning is also known as Aversive Conditioning.
First-Order and Second-Order Conditioning
First Order Conditioning.
•Bell + meat = salivation.
•Bell = Salivation.
Second Order Conditioning
(After first order
conditioning has occurred)
•Light + Bell = Salivation.
•Light = Salivation.
Learned Taste Aversions
• When it comes to
food being paired
with sickness, the
conditioning is
incredible strong.
• Even when food and
sickness are hours
apart.
• Food must be salient
(noticeable.)
Garcia and Koelling Study
• Studied rats and
how they make
associations.
• Some associations
seem to be adaptive.
CS
UCS
Learned Response
Loud Noise
Shock
Fear
Loud Noise
Radiation (nausea)
Nothing
Sweet Water
Shock
Nothing
Sweet Water
Radiation (nausea)
Avoid Water
Operant Conditioning
The Learner is NOT passive.
Learning based on consequence!!!
The Law of Effect
Click picture to see a better
explanation of the Law of Effect.
• Edward Thorndike
• Locked cats in a cage
• Behavior changes because
of its consequences.
• Rewards strengthen
behavior.
• If consequences are
unpleasant, the StimulusReward connection will
weaken.
• Called the whole process
instrumental learning.
B.F. Skinner
• The Mac Daddy of
Operant
Conditioning.
• Nurture guy through
and through.
• Used a Skinner Box
(Operant
Conditioning
Chamber) to prove
his concepts.
Skinner Box
Reinforces
• A reinforcer is anything
the INCREASES a
behavior.
Positive Reinforcement:
• The addition of something
pleasant.
Negative Reinforcement:
• The removal of something
unpleasant.
• Two types of NR
• Escape Learning
• Avoidance Learning
(Getting kicked out of class
versus cutting class)
Positive or Negative?
Putting your seatbelt on.
Faking sick to
avoid AP Psych
class.
Studying for a test.
Having a headache and
taking an aspirin.
Breaking out
of jail.
Getting a kiss
for doing the
dishes.
Punishment
Meant to decrease a
behavior.
Positive Punishment
• Addition of something
unpleasant.
Negative Punishment
(Omission Training)
• Removal of something
pleasant.
Punishment works best
when it is immediately
done after behavior
and if it is harsh!
How do we actually use Operant
Conditioning?
Do we wait for the
subject to deliver the
desired behavior?
Sometimes, we use a
process called
shaping.
Shaping is reinforcing
small steps on the way
to the desired
behavior.
To train a dog to get
your slippers, you would
have to reinforce him in
small steps. First, to
find the slippers. Then
to put them in his
mouth. Then to bring
them to you and so
on…this is shaping
behavior.
To get Barry to become a better student, you
need to do more than give him a massage when
he gets good grades. You have to give him
massages when he studies for ten minutes, or
for when he completes his homework. Small
steps to get to the desired behavior.
Chaining Behaviors
• Subjects are taught a
number of responses
successively in order
to get a reward.
Click picture to see a rat chaining behaviors.
Click to see a cool example of chaining behaviors.
Same Terminology as Classical
Conditioning
• Acquisition
If I wanted to
• Extinction
reinforce my son’s
dancing by giving him • Spontaneous
Recovery
lollipops when he
• Generalization
dances. Identify
the following….
• Discrimination
Primary v. Secondary Reinforcers
Primary Reinforcer
• Things that are in
themselves rewarding.
Secondary Reinforcer
• Things we have learned to
value.
• Money is a special
secondary reinforcer
called a generalized
reinforcer (because it
can be traded for just
about anything)
Token Economy
• Every time a desired
behavior is performed,
a token is given.
• They can trade tokens
in for a variety of
prizes (reinforcers)
• Used in homes, prisons,
mental institutions and
schools.
Premack Principle
Pat’s Hubbas might
be a great positive
reinforcer for me,
but it would not
work well on a
vegetarian.
• You have to take
into consideration
the reinforcers
used.
• Is the reinforcer
wanted….or at least
is it more preferable
than the targeted
behavior.
Reinforcement Schedules
How often to you give
the reinforcer?
• Every time or just
sometimes you see
the behavior.
Continuous v. Partial
Reinforcement
•
•
•
•
Continuous
Reinforce the behavior
EVERYTIME the behavior
is exhibited.
Usually done when the
subject is first learning
to make the association.
Acquisition comes really
fast.
But so does extinction.
Partial
• Reinforce the behavior
only SOME of the times
it is exhibited.
• Acquisition comes more
slowly.
• But is more resistant to
extinction.
• FOUR types of Partial
Reinforcement
schedules.
Ratio Schedules
Fixed Ratio
• Provides a
reinforcement after a
SET number of
responses.
Variable Ratio
• Provides a
reinforcement after a
RANDOM number of
responses.
• Very hard to get
acquisition but also very
resistant to extinction.
Fixed Ration- She gets a manicure for every 5
pounds she loses.
Interval Schedules
Fixed Interval
Variable Interval
• Requires a SET amount
of time to elapse before
giving the
reinforcement.
• Requires a RANDOM
amount of time to elapse
before giving the
reinforcement.
• Very hard to get
acquisition but also very
resistant to extinction.
Fixed Interval: She gets a
manicure for every 7 days she
stays on her diet.
Observational Learning
• Albert Bandura and his
BoBo Doll
• We learn through
modeling behavior from
others.
• Observational learning +
Operant Conditioning =
Social Learning Theory
Click pic to see some observational learning.
Latent Leaning
Edward Toleman
Three rat experiment.
Latent means hidden.
Sometimes learning is
not immediately
evident.
• Rats needed a reason
to display what they
have learned.
•
•
•
•
Insight Learning
• Wolfgang Kohler and
his Chimpanzees.
• Some animals learn
through the “ah ha”
experience.
Click pic to see insight learning.