191H@13

Contingency and contiguity

1) for many years it was assumed that the critical determinant of Pavlovian conditioning essential,

was the pairing of the CS and UCS in close temporal contiguity. (trace, elayed, backward ISI effects)

2) Recently, Robert Rescorla put this long held notion to task by suggesting that contingency not continuity was the determinant factor for learning.

Conditioning depends on the CS allowing the subject to predict the occurrence

of the UCS.

Following example: have contiguity in all of following groups

1) p CS/UCS > p no CsS/UCS = +1.0 acquisition

2) p CS/UCS < p no CS/UCS =-1.0 extinction

3) p CS/UCS = p no CS/UCS = .5

notice that number 3 has been brought up as a possible control group for Pavlovian conditioning. Random presentations.

Rescorla Predictability and number of pairings

Three groups of dogs Sidman avoidance trained. so it starts off with an instrumental task where escape conditioning is presented. Shock, hurdle, escape. And back again.

Now to a Pavlovian fear conditioning situation.

Group 1 CS UCS information > .5 acquisition P or Paired

Group 2 CS not paired <.5 U or unpaired

Group 3 Css and UCSs occurred random R or random

random and independent and non-contingent

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Results

Avoidance: P > U , produced increases and decreases in avoidance but R group produced no effect on learning or avoidance.

Inhibition and excitation.

Ramification: leaned helplessness

Rescorla suggest that this is the best control for classical conditioning was sensitization and pseudoconditioning but not random presentation control

Seligman a fellow U Penn Mafia does chronic fear produced by unpredictable

All groups bar press for food

P shock group

U paired shock

now to skinner box

P group

BAR PRESS learned

and received CSs either paired or unpaired with UCS/shock

R group stop bar pressing

develop ulcers.

Chronic fear produced by unpredictable shock (1968)

The dysfunctional .5

Ramifications: conditioned neurosis

physical and psychological control is lost

child abuse

bonaventure

welfare

soviet union