General Psychology: Introduction (II)

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Learning
Chapter 5
Part I
William G. Huitt
Last revised: May 2005
The Reality of Humankind
Humanity
Animal
Vegetable
Mineral
Psychology, Sociology, Anthropology
Zoology
Botany
Physics, Chemistry
Animals vs Human
• Share with animals
– Learning through respondent (classical)
conditioning (Pavlov)
– Learning through instrumental (operant)
conditioning (Watson, Thorndike, Skinner)
– Similar
•
•
•
•
Sensation and perception
Memory and reasoning
Affect and emotions (Freud)
Develop relationships with others (Erikson)
Animals vs Human
• Unique to humans
– Create symbols for realities; abstract symbolic
thought as mature adults (Piaget)
– Conscious, self-reflection (Bandura)
– Plan alternate strategies, engage in forethought
(Intelligence, Sternberg, Gardner)
– Regulate own behavior (Dweck, Bandura)
– Search for meaning (Frankl)
– Susceptible to subtle spiritual influences
(transpersonal, Maslow)
Learning
• A relatively permanent change in behavior or
behavior potential (i.e., knowledge, capability,
or attitude) that is acquired through experience
or practice and cannot be attributed to illness,
injury, or maturation.
• Behavioral definition would focus exclusively
on overt or measurable behavior
• Behaviorists recognize that learning is an
internal event. However, it is not recognized as
learning until it is displayed by overt behavior.
Behavioral Learning Theory
The behavioral learning theory is represented
as an S-R paradigm. The organism is treated
as a “black box.” We only know what is going
on inside the box by the organism’s overt
behavior.
Stimulus
Organism
Response
(S)
(O)
(R)
Classical Conditioning
• Classical conditioning
– A learning process through which one stimulus
comes to predict the occurrence of another stimulus
and elicits a response similar to or related to the
response evoked by that stimulus
• Stimulus
– Any event or object in the environment to which an
organism responds; plural is “stimuli”
Classical Conditioning
• Pavlov was studying the digestive system of
dogs and became intrigued with his observation
that dogs deprived of food began to salivate
when one of his assistants walked into the room.
• He began to investigate this phenomena and
established the laws of classical conditioning.
• Skinner renamed this type of learning
"respondent conditioning” since in this type of
learning, one is responding to an environmental
antecedent.
Classical Conditioning
• General model: Stimulus (S) elicits >Response (R)
• Classical conditioning starts with a reflex (R): an
innate, involuntary behavior.
• This involuntary behavior is elicited or caused by
an antecedent environmental event.
• Example: air is blown into your eye, you blink.
You have no voluntary or conscious control over
whether the blink occurs or not.
Classical Conditioning
The specific model for classical conditioning is:
• A stimulus will naturally (without learning)
elicit or bring about a reflexive response
• Unconditioned Stimulus (US) elicits >
Unconditioned Response (UR)
Classical Conditioning
Unconditioned
Stimulus (US)
Food
Unconditioned
Response (UR)
Salivation
Loud noise
Startle
Light in eye
Contraction of
pupil
Eyeblink
response
Puff of air in eye
Classical Conditioning
The specific model for classical conditioning is:
• Neutral Stimulus (NS) --- does not elicit the
response of interest
• This stimulus (sometimes called an orienting
stimulus as it elicits an orienting response) is a
neutral stimulus since it does not elicit the
Unconditioned (or reflexive) Response.
Classical Conditioning
The specific model for classical conditioning is:
• The Neutral/Orienting Stimulus (NS) is
repeatedly paired with the
Unconditioned/Natural Stimulus (US).
Classical Conditioning
• The Neutral Stimulus (NS) is transformed into
a Conditioned Stimulus (CS).
• That is, when the CS is presented by itself, it
elicits or causes the CR (which is the same
involuntary response as the UR.
• The name changes because it is elicited by a
different stimulus.
• This is written CS elicits > CR.
Classical Conditioning
• John Watson and emotional conditioning
– Little Albert (a healthy and emotionally stable
11-month-old infant) showed no fear except
of the loud noise Watson made by striking a
hammer against a steel bar near Albert’s
head
Classical Conditioning
Classical Conditioning
• In the area of classroom learning, classical
conditioning is seen primarily in the
conditioning of emotional behavior.
• Things that make us happy, sad, angry, etc.
become associated with neutral stimuli that
gain our attention.
Classical Conditioning
Example:
• Child is harassed at school
• Child feels bad when harassed
• Child associates being harassed
and school
• Child begins to feel bad when she
thinks of school
Classical Conditioning
In order to extinguish the associated of feeling
bad and thinking of school, the connection
between school and being harassed must be
broken.
Classical Conditioning
• John Watson and emotional conditioning
– Watson also had ideas for removing fears and laid
the groundwork for some behavior therapies used
today
– Peter (3-year-old who was afraid of rabbits) was put
in a high chair and given candy while a rabbit was in
a cage at a safe distance from him
– The rabbit was moved closer with each session
– Some of Peter’s friends were brought in to play with
the rabbit to show Peter first-hand that the rabbit
was safe
– By the end of the sessions Peter lost his fear of
rabbits
Classical Conditioning
• Biological predispositions
– Research has shown that humans are more easily
conditioned to fear stimuli, such as snakes, that can
have very real negative effects on their well-being
– Martin Seligman
• Said that the most common fears “are related to the
survival of the human species through the long course of
evolution”
• Suggested that humans and other animals are prepared to
associate only certain stimuli with particular consequences
Classical Conditioning
• Biological predispositions
– Taste aversions
• The dislike and/or avoidance of a particular food that has
been associated with nausea or discomfort
Classical Conditioning
• Biological predispositions
– Garcia and Koelling
• Exposed rats to a three-way conditioned stimulus: a bright
light, a clicking noise, and flavored water
• For one group of rats, the unconditioned stimulus was
being exposed to X-rays or lithium chloride, either of which
produces nausea and vomiting several hours after
exposure; for the other group, the unconditioned stimulus
was an electric shock to the feet
• The rats in one group associated nausea only with the
flavored water; those in the other group associated electric
shock only with the light and the sound
Classical Conditioning
• Biological predispositions
– Garcia and Koelling
• Garcia and Koelling’s research established two exceptions
to traditional ideas of classical conditioning
– First, the finding that rats formed an association
between nausea and flavored water ingested several
hours earlier contradicted the principle that the
conditioned stimulus must be presented shortly before
the unconditioned stimulus
– The finding that rats associated electric shock only with
noise and light, and nausea only with flavored water,
revealed that animals are apparently biologically
predisposed to make certain associations and that
associations between any two stimuli cannot be readily
conditioned
Classical Conditioning
• Biological predispositions
– Gustavson and others
• Used taste aversion conditioning to stop wild coyotes from
attacking sheep in the western United States
• Set out lamb flesh laced with lithium chloride, a poison that
made the coyotes extremely ill but was not fatal
• After only one or two experiences, the coyotes would get
sick even at the sight of a lamb
Classical Conditioning
• Biological predispositions
– Bernstein and others
• Devised a technique to help cancer patients avoid
aversions to desirable foods
• A group of cancer patients were given a novel-tasting,
maple-flavored ice cream before chemotherapy
• The nausea caused by the treatment resulted in a taste
aversion to the ice cream
• Researchers found that when an unusual or unfamiliar food
becomes the “scapegoat,” other foods in the patient's diet
may be protected and the patient will continue to eat them
regularly
Classical Conditioning
• Classical conditioning in everyday life
– Research suggests that the inability to acquire
classically conditioned responses may be the first
sign of Alzheimer’s disease, a sign that appears
prior to any memory loss
– Emotional behavior very susceptible to classical
conditioning
– Through classical conditioning, environmental cues
associated with drug use can become conditioned
stimuli and later produce the conditioned responses
of drug craving
Classical Conditioning
• Neurological basis of classical conditioning
– An intact amygdala is required for conditioning of
fear in both humans and animals, and context fear
conditioning further depends on the hippocampus
– Research clearly indicates that the cerebellum is the
essential brain structure for motor conditioning and
also the storage site for the memory traces formed
during such conditioning
Classical Conditioning
• Factors influencing classical conditioning
– There are four major factors that facilitate the
acquisition of a classically conditioned response
• How reliably the conditioned stimulus predicts the
unconditioned stimulus
• The number of pairings of the conditioned stimulus and the
unconditioned stimulus
• The intensity of the unconditioned stimulus
• The temporal relationship between the conditioned
stimulus and the unconditioned stimulus
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