Classical Conditioning
Dr. Ilija Gallego
Dr. Ilija Gallego
1
CLASSICAL
CONDITIONING
The Simplest Type of
Learning:
Pavlovian or Respondent
Conditioning
Dr. Ilija Gallego
2
Vocabulary

Conditioned = “learned”



A conditioned stimulus is one we learn to
respond to
A conditioned response is a learned response
Unconditioned = “unlearned” or
inborn


An unconditioned stimulus is one we naturally
must respond to
An unconditioned response is a response we
naturally make
Dr. Ilija Gallego
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Stimulus To Response

Classical conditioning is based on
Stimulus > Response

A stimulus in anything you can pick up
on using your senses

The response is what you do as a result
of coming into contact with a stimulus
Dr. Ilija Gallego
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Responses in Classical Conditioning

The responses in classical conditioning are
all internal, involuntary, automatic,
reflex type responses.

This is true of the unconditioned
response (UR) and the conditioned
response (CR)
Dr. Ilija Gallego
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Learning by Association



In classical conditioning the learner learns by
association.
An association is involuntarily made between 2
stimuli.
The association occurs because we pair a
stimulus that always leads to an involuntary
response (an unconditioned stimulus - US), with
a stimulus that leads to no particular response (a
neutral stimulus - NS)
Dr. Ilija Gallego
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EXAMPLES OF
UNCONDITIONED REFLEXES
US
Onion juice
Food
Touching hot object
Extreme heat
Extreme cold
Increase in light
Puff of air aimed at eye
Loss
Pain
UR
Tearing
Salivating to food
Pulling away from object
Sweating
Shivering
Contracting Pupils
Blinking
Sadness at loss
Fear/Avoidance of pain
Dr. Ilija Gallego
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Before Conditioning (Learning)



A neutral stimulus (NS) (one that elicits no
response) is chosen. Example: a picture of an
onion.
An unconditioned stimulus (US) is chosen.
This is a stimulus that always leads to an
internal, involuntary, automatic, reflex type
response. Example: onion juice.
The US elicits an unconditioned response
(UR) (an internal, involuntary, automatic, reflex
type response). This is the unconditioned
(unlearned) response. Example: eyes tear up to
onion juice.
Dr. Ilija Gallego
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During Conditioning
The neutral stimulus (picture of the onion)
is paired with the US (onion juice).
 The US elicits an UR. The UR is an
internal, involuntary, automatic and
INBORN response. (The onion juice causes
eyes to tear up.)
 The pairing of the stimuli (the picture and
the onion juice) is usually done
repeatedly.

Dr. Ilija Gallego
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After Conditioning



The neutral stimulus (the picture of the onion) is
presented alone.
If it elicits a response (if the learner’s eyes tear
up to the picture of the onion), then it is no
longer neutral; the learner has learned to
respond to this stimulus.
The response elicited is internal, involuntary,
automatic and reflex like, but it is not inborn –
it is LEARNED. We call this the conditioned
(learned) response (CR).
Dr. Ilija Gallego
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Analysis to Pavlov’s Work

Before Conditioning
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During Conditioning
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Bell (Neutral Stimulus) > No response
Food (US) > Salivation to Food (UR)
Bell (NS) is Paired with the Food (US) >
Salivation to Food (UR)
After Conditioning


Bell > Salivation to the Bell (CR)
The bell is no longer a NS, but has become a
CS
Dr. Ilija Gallego
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11
Extinction
Pairings of the CS and US lead to
conditioning whereas presentation of
the CS only leads to loss of the
conditioned response
 Extinction refers to loss of CR due to
the CS presented without the US
 Extinction is useful in clinical situations


Extinction of a phobia can be treated by
exposure to the CS only
Dr. Ilija Gallego
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Spontaneous Recovery

Sometimes after extinction the CR
returns.

This shows us that the response is gone
but not forgotten.

The learner does not think, “Oh, there is
the CS, I’ll make a CR now.” There is no
thinking involved in classical conditioning.
Instead the CR is made involuntarily.
Dr. Ilija Gallego
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Conditioning of Emotional
Responses

John Watson documented that conditioning of
emotional responses in the Little Albert study
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NS/CS: a white rat
US: a loud banging sound
UR: fear/startle response
Eventually Albert exhibited a learned fear (CR) to the
white rat (NS became the US)
Other instances of classical learning

Positive: conditioning of attraction in advertising


Brand name (CS) + model (US) => positive reaction to
product
Negative: aversion

Flavor (CS) + illness (US) => flavor aversion
Dr. Ilija Gallego
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Generalization

This is when the learner makes a CR to
a stimulus that is not the CS, but is
similar to it.

Examples

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Pavlov’s dogs salivate to a tone that is similar
to the bell, but is not the original bell
A person becomes afraid of all dogs (or some
dogs) after being bitten by one dog.
Little Albert became afraid of white furry
things
Dr. Ilija Gallego
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Discrimination

The learner distinguishes between the
CS and other similar stimuli. S/he
responds (makes a CR) only to the CS.

Examples

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Pavlov’s dogs are taught to salivate to “ding”
but not to “dong.”
A person becomes afraid of only the dog that
bit him/her.
Dr. Ilija Gallego
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4 FACTORS INFLUENCING
CLASSICAL CONDITIONING
1.
Number of pairings (learning trials)
between the US and the CS
More trials leads to stronger CR
2. Intensity of the US
Higher intensity leads to stronger CR
and faster learning of CR
Dr. Ilija Gallego
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4 Factors Influencing CC
3. Consistency of the CS and US
pairings
Higher consistency leads to more
consistent and stronger CR
4. Temporal relationship (timing)
between the CS and the US
Dr. Ilija Gallego
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4 Subtypes of Classical Conditioning

Based on the temporal relationship
between the CS and the US
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Delayed Conditioning
Trace Conditioning
Simultaneous Conditioning
Backwards Conditioning
Dr. Ilija Gallego
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Delayed Conditioning

Bell (CS) is rung BEFORE AND DURING
the time that the food (US) is given

Bell (CS) comes BEFORE the food (US)

Presentation of bell (CS) OVERLAPS with
the presentation of the food (US)
Dr. Ilija Gallego
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Trace Conditioning

Bell (CS) is rung BEFORE BUT NOT
DURING the time that the food (US) is
given

Bell (CS) comes BEFORE the food (US)

Presentation of bell (CS) DOES NOT
OVERLAP with the presentation of the food
(US)
Dr. Ilija Gallego
21
Simultaneous Conditioning

Bell (CS) is rung only DURING the time
that the food (US) is given

Bell (CS) comes with, but NOT BEFORE
the food (US)

Presentation of bell (CS) OVERLAPS with
the presentation of the food (US)
Dr. Ilija Gallego
22
Backwards Conditioning

Bell (CS) is rung AFTER the food (US) is
given

Bell (CS) DOES NOT COME BEFORE the
food (US)

Presentation of bell (CS) DOES NOT
OVERLAP with the presentation of the food
(US)
Dr. Ilija Gallego
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Determining the Effectiveness of the
Subtypes

Does the subtype allow for the learner to
passively ANTICIPATE what they are
focused on (the US or food)?


The CS must come before the US
Does the subtype maximize the likelihood
that the learner will make a passive
ASSOCIATION between the CS (bell) and
the US (food)?

The CS and US must overlap in time
Dr. Ilija Gallego
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Evaluating the Effectiveness of the
Subtypes

Delayed: anticipation & association
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Trace: anticipation, but not association
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Somewhat effective
Simultaneous: association, but not
anticipation

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Most effective
Not very effective
Backwards: neither anticipation, nor
association

Barely effective or completely ineffective
Dr. Ilija Gallego
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Exceptions to the Rule:
One Trial Learning

Some CRs can be learned after only one
pairing between the NS and the US

Example: Learning to fear a dog or all dogs
from having been bitten once

Nonetheless, more pairings does lead to
stronger learning. How afraid of dogs would
you be if you were repeatedly bitten?
Dr. Ilija Gallego
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Exceptions to the Rule:
Taste Aversion

Learning to dislike a food or taste often
happens in only one trial.

Typically it happens in a trace conditioning
pattern, but the time between having a
certain food or taste and becoming ill can
be as long as 12 hours, and we might still
develop the taste aversion.
Dr. Ilija Gallego
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Summary of Classical Conditioning
Learning occurs through pairing 2 stimuli
 Responses, both inborn (UR) and learned
(CR) are involuntary, automatic, internal.
 No thinking is involved.
 Learner is passive
 Learner is focused on the US
 Responses learned include only simple
responses such as reflexes, likes and
dislikes, fears and emotional responses

Dr. Ilija Gallego
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