Chapter 6: Learning - Steven-J

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Transcript Chapter 6: Learning - Steven-J

Chapter 6: Learning
Section 1: Classical Conditioning
Classical Conditioning Terms
1. Stimulus = Anything that produces a reaction (response)
from a person or animal
2. Conditioning = A fancy word for learning that occurs
through the pairing of different stimuli
*When 2 stimuli have been associated together and one
stimuli leads to the response for the other, we call that
classical conditioning
Stimuli and Response
Stimulus
Response
Ivan Pavlov
I. Ivan Pavlov Rings a Bell (1/3)
A. A Russian psychologist who learned that not
only humans, but also dogs, can learn to
associate one thing with another. This is
especially true when food is involved.
I. Ivan Pavlov Rings a Bell (2/3)
i. In particular, he studied salvation (or mouth
watering) in dogs
ii. He already knew that dogs would salivate if meat
was placed before them; therefore, meat is a
stimulus for the response of saliva
iii. What he observed, however, is that they did not
always wait for the meat to begin salivating. In
fact, they would salivate when they heard bowls
clinking/can opener
Experiment Setup
I. Ivan Pavlov Rings a Bell (3/3)
iv. He then began to question if they would salivate
to any stimulus that signaled meat. He chose to
use a bell.
v. He trained them by ringing a bell and then
presenting them with meat powder. After
repeating this several times, he removed the
meat and the dogs would salivate only to the bell.
Results
II. US, UR, CR, and CS: Letters
of Classical Conditioning (1/2)
A. US = Unconditioned Stimulus, and is the
stimulus causing a response that is automatic:
In Pavlov’s experiment this was the meat
B. UR = Unconditioned Response, and refers to
the automatic response: In Pavlov’s
experiment, this was salivation
II. US, UR, CR, and CS: Letters
of Classical Conditioning (2/2)
C. CR = Conditioned Response and is the learned
response to a stimulus that was previously
neutral: In Pavlov’s experiment this was
salivation in the response to the bell
D. CS = Conditioned Stimulus and is the learned
stimulus that was previously neutral: In
Pavlov’s experiment this was the bell
III. Adapting to the Environment
1. Classical Conditioning is important because it
helps us avoid death or deal with danger
Ex. A new car owner may hear his or her car alarm
go off (CS). Thinking that someone is breaking
into the car (US), the car owner calls the police
(CR).
A. Taste Aversion
i. Taste Aversion is a learned avoidance of a
particular food
a. Ex – If you ate at Duke’s sandwiches and
you got sick later you probably wouldn’t
want to eat there anymore
b. Significant because unlike Pavlov and the
dogs, it only takes one time to create the
aversion to food
B. Extinction
i. When a Conditioned Stimulus
is no longer followed by it’s
unconditioned stimulus, then it
will no longer lead you the
conditioned response
a. If your car alarm goes off
every night, you get used to
it and never think that your
car has been broken into
C. Spontaneous Recovery
i. This is the display of a response that was
previously extinct
a. Typically when it returns, the response will be
weaker
b. Ex – You hear the same song over and over
again it gets really old (You stop enjoying it.
No feelings, etc…) Well 5 years later you
hear it and enjoy it again
D. Generalization and Discrimination
(1/2)
i. Generalization is responding to
similar stimuli the same way
even though they aren’t the
same
a. Ex – You get sick off of
chocolate ice cream.
Even though it’s not
chocolate, you can’t
eat vanilla ice cream
without getting sick.
=
D. Generalization and Discrimination
(2/2)
ii. Discrimination is being able to
respond differently to stimuli
that are not similar to each
other
a. Ex – An orange t-shirt and
an orange polo aren’t the
same
≠
Applications of Classical
Conditioning
 Classical conditioning becomes major
avenue for learning in our daily lives
 Can be used to solve problems




Flooding
Systematic Desensitization
Counterconditioning
Bell-and-Pad Method for Bedwetting
Flooding
 Many of us have common fears that are
out of proportion of actual harm (heights,
snakes, speaking in public, etc.)
 In flooding, exposed to harmful stimulus
until no fear

Ex. Put in room with a lot of snakes
 Effective but unpleasant
Systematic Desensitization
 Taught relaxation techniques; then
gradually exposed to fear as relaxed
 Takes longer than flooding but not as
unpleasant

Ex. When relaxed look at picture of snake;
gradually look at real snake
Counterconditioning
 Can cookies help children overcome
fears?
 A pleasant stimulus is paired repeatedly
with a fearful one; counteracting fear
 The good is so good; you don’t notice
bad

Fed cookies while exposed to rabbits
Bell-and-Pad Method for BedWetting
 Children sleep on special pad; when
starts to urinate the water triggers a bell
 The bell becomes the unconditioned
stimulus (US) based on child’s biological
makeup [people wake up to loud noises]
 Because you pair the bell (US) with
bladder tension (CS) you thus wake up
due to bladder tension (CR)
Operant Conditioning
 Another type of learning; we learn from
our behaviors
 People learn to do or not do certain
things because of the results
 You do things with desirable
consequences; don’t do with undesirable
consequences
B.F. Skinner and Project
Pigeon
 During WWII, proposed training pigeons
to guide missiles to target
 Would be given food pellets for pecking
at the targets; peck at certain targets to
guide missile
Reinforcement
 A stimulus *increases the chances of the
behavior causing it to happen again
 Ex. Child cleans room so his mom reads
him a story; cleans room more to get
more stories
Skinner Box
Types of Reinforcers
 Primary: function due to biological
makeup [food, warmth, water, etc.]

Don’t need to be taught the value of these
 Secondary: Value of these must be
learned [$, attention, and social
approval]


May be learned through chain of
associations
$ can be exchanged for food
Types of Reinforcers
 Positive reinforcer: increase the
frequency of a behavior

Not always constant – Food is good when
hungry; if not then won’t work
 Negative reinforcer: Unpleasant stimulus
that increases behavior when it is
removed [ex. Discomfort, fear, social
disapproval

Food in teeth
floss more
floss takes it out
Rewards and Punishment
 Reward: Increased frequency of
behavior [most commonly synonymous
with positive reinforcement]
 Punishment: applied to decrease
frequency of behavior (usually
unpleasant)

Litter
Fined $
Don’t Litter
Problems with Punishment
1. Learn what not to do but don’t learn
2.
3.
4.
5.
what to do
Only works when punished every time
May simply try to leave situation rather
than change behavior [avoid
punishment]
Creates anger and hostility
May be imitated as way of solving
problems [Parents hit if misbehave
Now kid hits their kids/friends if
misbehaving]
Schedules of Reinforcement
 When and how often the reinforcement
occurs
 Continuous Reinforcement: Every time a
behavior occurs

Problem: behavior quickly returns when
reinforcement disappears
Schedule of Reinforcement
 Partial Reinforcement: Not every time

You don’t like every movie you see, but
continue to go because you like some of
them
Interval Schedule - amt. of time
that must elapse btw. Reinforcements
“How much time has gone by?”
 Fixed-interval: fixed amount of time

Quiz every Friday therefore anticipate by
studying every Thursday
 Variable-interval: Varying amount of time

Timing of next reinforcement is
unpredictable [Pop Quizzes]
Ratio Schedules –
“How many times it occurs?”
 Fixed or variable:

Fixed: reinforcement is provided after a
fixed number of correct responses
 You
get a free sub from Subway after buying
ten

Variable: reinforcement is provided after a
variable number of correct responses
 Can’t

predict; number changes every time
High response rate however: Slot machines
Extinction of Operant
Conditioning
 Gain from repeated performance of a
behavior without reinforcement
 Ex. If studied for test but then did poor;
start to wonder if studying really helped;
wasn’t reinforced
Application of Operant
Conditioning
 Shaping: reinforce small steps in right
direction

Break a difficult/complex task into smaller
parts

Ex. Riding a bike – you don’t start off flying
around on two wheeler
Program Learning
 Based off shaping; Computer-based
 Reinforces correct responses by not
letting you finish/continue until you have
100% correct
 Doesn’t punish for mistakes; simply
reinforces correct responses