Extinction of Conditioned Behavior

• Effects of Extinction

• Extinction and Original Learning

• Paradoxical Effects in Extinction

Effects of Extinction

Extinction involves omitting the US or reinforcerCS alone, no US R alone, no outcome

Two main effects of extinction procedures on behavior

responding decreases response variability increases

Extinction and Original Learning

• Spontaneous Recovery

• Rapid Reacquisition

• Renewal

• Reinstatement

Spontaneous Recovery

CS1 – USCS2 – US

AcquisitionExtinction 1

Extinction 2

Wait

Test

CS2 – nothCS1 ?CS2 ?

CS1 – noth 2 weeks

Longer wait after extinction, more spontaneous recovery

Spontaneous Recovery

Shows importance of passage of time

Renewal

Context A

Pairings Extinction CS Test

Context AContext B

A return to the context of acquisition after extinction of the CRin a different context causes CR recovery (ABA renewal)

No Extinction

Context A

Renewal

Mechanisms• Subjects turn to the context to disambiguate the meaning

of the CS– CS->US in acquisition (A) – CS->no US in extinction (B)

• Inhibitory association is specific to Context B?– A change in context after extinction of the CR causes CR recovery

(ABA renewal)– ABC causes renewal, which suggests a return to Context A is not

necessary– AAB renewal– ABC renewal is normally weaker than ABA renewal, so a return

to the context of acquisition may play some role

Reinstatement

Context A

Pairings Extinction CS Test

Context A

A return of contextual excitation reinstates the extinguished CR

Context AContext AContext B

US alone

Reinstatement

Acquisition with Differing Percentage Schedules

Spee

d

Day

100%

80/50/30%

Extinction with DifferingPercentage Schedules

Spee

d

Day

80% 50% 30%

100%

Explanations

• Mowrer-Bitterman Discrimination Hypothesis

• Amsel’s Frustration Theory (Emotional)

• Capaldi’s Sequential Theory (Cognitive)

Theios ExperimentPHASE 1 PHASE 2 EXT

G1 100% 0%

G2 100% 100% 0%

G3 50% 100% 0%

G4 50% - 0%

Extinction Experiment

Extinction Trials

Spee

d

G1, G2 100%

PHASE 1 PHASE 2 EXT

G1 100% 0%

G2 100% 100% 0%

G3 50% 100% 0%

G4 50% - 0%

G3, G4 50%

Amsel’s Frustration Theory

Amsel’s Frustration Theory

100% Reinforcement Group

Amsel’s Frustration Theory

50% Reinforcement Group

Amsel (extinction data)

Extinction Trials

Spee

d

100% 50%

AmselEXT

BETWEEN SUBJECT

GROUP 1 T F 100%

T-

GROUP 2 N F 50%

N-

WITHIN SUBJECT

TRIALS 1,3,6….

TF 100%

T-

TRIALS2,4,5….

NF 50%

N-

Sequential Theory

• Memory of past nonreinforced responding during reinforcement– Number of NR transitions– Maximum N length– Variability of N length