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Schemas & Just world Belief Classical Conditioning Operant Conditioning
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Norms Social Influence & Obedience All Notes in one view

Section 2: Classical Conditioning

Important Abbreviations

CS  Conditioned Stimulus CR  Conditioned Response
UCS  UnConditioned Stimulus    UCR  UnConditioned Response
NS  Neutral Stimulus


Before Conditioning
Bell (NS) No salivation response
Food was presented (US) Naturally the animal salivates. (UCS)
After Conditioning
Bell (CS) Salivation response (CR)


Pavlov – Russian psyciologist who ivesigated classical conditioning
      Pavlov received the nobel prize for studing digestion: He put windows into the digestive tract of dogs and watched portions of the diegesiton process.  He also studied salivation which is part of digestion.  When he fed the animals, he measued saliva which was an unconditioned response

He found that sometimes when he would open the door and the dogs would begin salivating.  Aparently salivating in accordance to sounds which were associated with food.

Pavlov decided to study conditioning which is the most basic form of learning. - If across several trials you ring a bell just before you feed an animal eventually the bell will elicit salivation.

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Example of Classical Conditioning:  (Take careful note of the terminology used)

Bell (CS) is associated to Meat Powder (UCS) Salivation
N = Number of Trials

First taught, then do an extinction trial, then wait, until it is extinguished, then wait a day with out any trials, the spontaneous recovery of the Acquisition (or the re-appearnce of the conditioned stimulus) is smaller than the origional resopnse.


FIRST: (acquisition) A dog  is first taught the bell promises food and will salivate when the bell is rung, even before food is presented
SECOND: (Extinction) Now the scientist is trying to make the bell have no meaning.   To do this the scientist rings the bell but does not present any food.  After a few trials, the dog finally realizes the bell nolonger promises food, and therefore the dog stops salivating when the bell rings.
Third: (Spontaneous Recovery) which references the recovery of the acquisition.   After a rest period the conditioned resopnse is reseoted even after previous extinction.
Spontaneous recovery can be prevented by over extinction: continuing the extinction trials.


___ = Stimulus off
--- = Stimulus on
___---___ = [off on off] the --- is the duration of "on"
Our example is:
CS = Bell
US = Opening the Drawer containing Meat
Paradigm Time
Simultaneous Conditioning CS ____---____ - ring bell and open meat drawer
US ____---____
Delayed conditioning
        Strongest Conditioning
CS _------------_
US ______----_
Trace Conditioning CS __---______
US ______---__
Temporal Conditioning US __---__---__
Backward Conditioning CS ______---_
US ___---____
Stimulus Generalization

If you condition a dog on a bell with 5000 cycles per second and you use the same bell, you get the same response.
But if you ring a bell of 3000 cycles per second you get a diminished salivary resopnse in comparison to the bell which rang at 5000 cycles per second

To eliminate generalization and inhance descrimation:, give the animal food over several trials when the the 5,000c/s is rung; then ring bells with frequencies close to 5000c/s but never feed the dog, the dog will then lean to descrimate between a 5000c/s bell and other bells.

John Watson & his assistant Ms. Rayner

"Little Albert" Experiment - The conditioned fear of cute fuzzy animals

In the beginnning little albert played freely with a white rat.  But later, Watson paired a loud noise with the presntation of the rat.   Albert became afraid of the rat, and subsequently other small cute fuzzy animals.

Mary Cupboard Jones – helped with behavioral psychology and the treatement of phobias.  Invented systemeatic desensitization (a treatment for phobias)

Conditioned Food Aversion – if you get sick after eating something, there is a likelihood that you will not choose to eat it again, that is, you will aviod the food.

This was used by shepherds who wanted to protect their flock, they would put out some tainted meat (which made them sick), and the coyotes would get sick, there after no longer wanting sheep meat.

Conditioned Immune Resopnse - The immune resopnse can be classically conditioned. - Example: if a drug which lowers the immune system is paired over several trials with a specific taste (saccharin) the animal's immune system will be lowered by the taste alone.

Some animals which just get the flavor of a particularly averted food, the immune system goes down.

Homeostasis - an animal's body strives to maintain a constant physological state.
Conditioned Compensatory Resopnse (learned tollerance)

If a rat is put in a cold dark ice box, his body tempature drops.   After exposing the rat in this situation sevral times, it will be conditioned.

If the ice box is nolonger cooled and the rest of the situation remains the same, what will happen when the animal is put in the box? Will the animal's body temperature increase or will it decrease?

Paradoxically the animal's body temperature will increase!  

The rat's body will be tricked into compensating for the cold, even though there is none - his body temperature will therefor rise. This is an example conditioned compensatory response.

Tolerance – Decreased effectiveness of a drug through repeated exposure.
Learned tolerance Conditioned tollerance. Is created by a conditioned compensatory response.

Example: Some drugs have similar effects/problems… if a drug is taken the body will remember the environment in which the drug was taken, so if you usually take a drug with friends your body begins to build up a tollerance for the drug in the presence of the conditioned stimulus - friends, but later take it by your self, you have a higher likelihood of overdosing because the conditioned stimulus is absent, there is no conditioned compensatory response lessening the effect of the drug. 





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