What is Psychology?

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Learning
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Classical Conditioning
Classical Conditioning in Real Life
Operant Conditioning
Operant Conditioning in Real Life
Social-Cognitive Learning Theories
Learning
• Learning: A relatively permanent change
in behavior (or behavioral potential) due
to experience.
• Behaviorism: An approach to psychology
that emphasizes the study of observable
behavior and the role of the environment
as a determinant of behavior.
Classical Conditioning
• New Reflexes from Old
• Principles of Classical Conditioning
• What is Actually Learned in Classical
Conditioning
Pavlov’s Apparatus
• Ivan Pavlov(1849-1936) researched digestion
• Harness and fistula (mouth tube) help keep dog
in a consistent position and gather
uncontaminated saliva samples
– They do not cause the dog discomfort
– Dogs drooled before the food was presented
after having been in laboratory after only a
few times
– He called the phenomenon a conditional reflex
New Reflexes From Old
• Classical Conditioning: The process by which a
previously neutral stimulus acquires the capacity
to elicit a response through association with a
stimulus that already elicits a similar or related
response.
• Learning occurs when a neutral stimulus is
regularly paired with an unconditioned stimulus.
Conditioning Terms
• Unconditioned Stimulus:
– A stimulus that elicits a reflexive response in
the absence of learning.
• Conditioned Stimulus:
– An initially neutral stimulus that comes to
elicit a conditioned response after being
associated with an unconditioned stimulus.
• Unconditioned Response:
– A reflexive response elicited by a stimulus in
the absence of learning.
• Conditioned Response:
– A response that is elicited by a conditioned
stimulus; it occurs after the conditioned
stimulus is associated with an unconditioned
stimulus.
Principles of Classical
Conditioning
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Acquisition
Extinction
Higher-Order Conditioning
Stimulus Generalization and
Discrimination
Acquisition
• A neutral stimulus that
is consistently followed
by an unconditioned
stimulus will become a
conditioned stimulus.
• To be most effective the
stimulus to be
conditioned should
precede the
unconditioned stimulus
rather than follow it.
• The conditioned
stimulus becomes a
signal/predictor for the
unconditioned stimulus.
Extinction
• The weakening and
eventual
disappearance of a
learned response; in
classical conditioning,
it occurs when the
conditioned stimulus
is no longer paired
with the
unconditioned
stimulus.
Higher Order Conditioning
• A procedure in which a neutral stimulus becomes
a conditioned stimulus through association with
an already established conditioned stimulus.
Generalization and Discrimination
• Stimulus Generalization:
– After conditioning, the tendency to
respond to a stimulus that resembles
one involved in the original
conditioning.
• Stimulus Discrimination:
– The tendency to respond differently to
two or more similar stimuli.
Classical Conditioning
in Real Life
• Learning to Like
– Advertising
– Sales
• Learning to Fear
– See next Slide
• Accounting for Taste
• Reacting to Medical Treatments
Learning to Fear
• An 11-month old boy – named “Albert” – was conditioned
to fear a white laboratory rat
– Each time he reached for the rat, Watson made a loud
clanging noise right behind Albert
• Albert’s fear generalized to anything white and furry
– Including rabbits and Santa Claus
Counterconditioning
• In classical conditioning, the process of
pairing a conditioned stimulus with a
stimulus that elicits a response that is
incompatible with an unwanted
conditioned response.
Operant Conditioning
• The process by which a response becomes
more likely to occur or less so, depending
on its consequences.
• Behavior becomes more likely or less
likely, depending on its consequences
• Also referred to as instrumental
conditioning
The Consequences of Behavior
• Reinforcement:
– The process by which
a stimulus or event
strengthens or
increases the
probability of the
response that it
follows.
• Punishment:
– The process by which
a stimulus or event
weakens or reduces
the probability of the
response that it
follows.
Reinforcement
• Positive Reinforcement:
– The response is
followed by
presentation of, or
increase in intensity of,
a reinforcing stimulus.
• Negative Reinforcement:
– The response is
followed by removal,
delay, or decrease in
intensity of, an
unpleasant stimulus.
Punishment
• Positive Punishment:
– The response is
followed by
presentation of, or
increase in intensity of,
a punishing stimulus.
• Negative Punishment:
– The response is
followed by removal,
delay, or decrease in
intensity of, an pleasant
stimulus.
Principles of Operant
Conditioning
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Extinction
Stimulus generalization and discrimination
Learning on schedule
Shaping
Biological limits on learning
The “Skinner Box”
• When a rat in a
Skinner box presses a
bar, a food pellet or
drop of water is
automatically
released.
• Similar boxes exist for
pigeons and many
other species.
Learning on Schedule
• Continuous Reinforcement:
– A reinforcement schedule in which a
particular response is always
reinforced.
• Intermittent (Partial) Schedule of
Reinforcement:
– A reinforcement schedule in which a
particular response is sometimes but
not always reinforced.
Skinner: The Man and the Myth
• Burrhus Frederick Skinner,
1904-1990
– Better known as B.F.
Skinner
• Much misinformation is
circulated about his life
and work
– e.g., his daughters
grew up normal,
despite rumors that
they were
institutionalized
Operant Conditioning
in Real Life
• The Pros and Cons of Punishment
• The Problems with Reward
When Punishment Fails
• People often administer punishment
inappropriately or mindlessly.
• The recipient often responds with anxiety, fear,
or rage.
• The effectiveness can be temporary, and depend
on the presence of the person who administers
it.
When Punishment Fails
• Most misbehavior is hard to punish immediately.
• Punishment conveys little information.
• An action intended to punish may instead by
reinforcing because it brings attention.
Why Rewards Can Backfire
• Rewards must be tied to the behavior you
are trying to increase
• Extrinsic Reinforcers:
– Reinforcers that are not inherently
related to the action being reinforced,
such as money, prizes, and praise.
• Intrinsic Reinforcers:
– Reinforcers that are inherently related
to the action being reinforced, such as
enjoyment of the task and satisfaction
of accomplishment.
Turning Play Into Work
• When preschoolers were
promised a prize for
drawing with felt-tip
pens, the behavior
increased.
• After they got the
prizes, they spent less
time with pens than
before the study began.
Social-Cognitive Learning
Theories
• Learning by Observing
• Behavior and the Mind
Learning by Observing
• Observational Learning:
– A process in which an individual learns
new responses by observing the
behavior or another (a model) rather
than through direct experience;
sometimes called vicarious conditioning.
Latent Learning
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Rats: one maze trial/day
One group found food every time (red line)
Second group never found food (blue line)
Third group found food on Day 11 (green line)
– Sudden change, day 12
• Learning isn’t the same as performance
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