Transcript Learning: Operant Conditioning

Learning: Operant Conditioning
Operant Conditioning
 Suppose
your dog is wandering
around the neighborhood, sniffing
trees, checking out garbage cans,
looking for a squirrel to chase. A
kind neighbor sees the dog and
tosses a bone out the kitchen door
to it. The next day, the dog is likely
to stop at the same door on its
rounds, if not go to it directly. Your
neighbor produces another bone,
and another the next day. Your dog
becomes a regular visitor.
Operant Conditioning
 Suppose
you have a younger brother
who is unhappy because you seem to
be capturing your mother’s attention.
He begins to pout and act aggressively
toward you. Right away your mother
stops attending to you to reprimand him.
Even though your mother’s attention is
negative, your brother seems to like it.
A short time later, he is back harassing
you and earning another reprimand
from your mother.
Operant Conditioning
Operant Conditioning – learning from the
consequences of behavior.
 The term operant is used because the subject
operates on or causes some change in the
environment. This produces a result that
influences whether they will operate or
responds the same way in the future.
 Depending on the effect of the operant
behaviors, the learner will repeat or eliminate
these behaviors – to get the rewards or avoid
punishment.

E.L.Thorndike
 E.L.
Thorndike
was the first
person to study
how behavior
is shaped by
consequences.
E.L. Thorndike

He placed a hungry cat in a
puzzle box with food outside.
 On the first few trials the cat
engages in several
behaviors: scratching,
meowing, sniffing, grooming,
and pulling a string.
 Pulling at the string enables
the cat to escape and access
food.
 Over a series of trials, the
time taken for the cat to
escape decreases.
E.L. Thorndike
of Effect – behaviors followed by
positive consequences are
strengthened, while behaviors followed
by negative consequences are
weakened.
 Thorndike’s findings were significant
because they suggested that the law of
effect was a basic law of learning and
provided an objective procedure to study
it.
 Law
B.F. Skinner
 B.F.
Skinner is the
psychologist most
closely
associated with
operant
conditioning.
 He coined the
term operant
conditioning.
B.F. Skinner
He developed the “Skinner Box.”
 The box is empty except for a bar and an
empty cup below.
 He places a hungry rat in the box.
 If the rat presses the bar and it is followed by
food, the consequence increases the chance
the rat will press the bar again.
 The box measures the number of bar presses
over a certain period of time

Skinner Box
Principles and Procedures
 With
the Skinner Box, the rat will learn to
press the bar to get food. This is a type
of reinforcement.
 Reinforcement – a consequence that
occurs after a behavior and increases the
chance that the behavior will occur again.
 Examples of consequences that people
respond to are social approval, money,
and extra privileges.
 A procedure in which an experimenter
successively reinforces behaviors that
lead up to the desired behavior is known
as shaping.
Principles and Procedures
Two Basic Classes of Reinforcement
 1. Reinforcement Procedures – always
leads to an increase in response.
Reinforcement – a reward stimulus
that increases the probability that a
behavior will occur again.
 Negative Reinforcement – an aversive
stimulus whose removal increases the
likelihood that the preceding response will
occur again.
 Positive
Principles and Procedures
 Besides
positive and negative
reinforcers, there are also primary
and secondary reinforcers.
 Primary reinforcer – a stimulus,
such as food, water, or sex, that is
innately satisfying and requires no
learning to become pleasurable.
 Secondary reinforcer – any
stimulus that has acquired its
reinforcing power through learning.
Principles and Procedures
Punishment Procedures – always leads
to a decrease in response.
 2.
punishment – when you perform a
behavior then something bad happens.
 Negative punishment – when you perform a
behavior then something good is taken away.
 Positive
 Although
somewhat confusing, remember
that positive and negative punishment
decrease the likelihood of a behavior
occurring again, while positive and
negative reinforcement increase the
likelihood of a behavior occurring again.