Extinction
removal of the outcome when it previously occurred
- reducing CR by presenting CS without US
Behavioral variability
different levels of responding from same subject
Applied significance
- exposure therapies
forms of recovery from extinction
- spontaneous recovery
- renewal
- reinstatement
what does recovery show us
shows that extinction does not eliminate prior learning
- not unlearning!
Spontaneous recovery
A return in conditioned response following the passage of time after extinction
Study of spontaneous recovery
- Rescorla 2004
- extinguished two stimuli, and tested them after 1 day vs 8 days
- after 8 days it had more recovery
who first observed spontaneous recovery
pavlov
- but he though it was inhibition that temporarily was by excitation
renewal effect
A recovery of conditioned responding when the contextual cues that were present during extinction are changed
ABA technique
- technique for testing renewal effect
- condition in A, extinguish in B and test in A
- testing in A will retrieve contextual cues that will cause recovery
who did the ABA design
- Bouton 2008
Why have a control in ABA design
to ensure that responses were not due to excitatory associations between the CR and place.
- A goup that was extinguished in the same context A, had the same results as the test group.
ABC experiment
- condition in A, extinguish in B, and test in C
- shows that responding memories are harder to retrieve when tested in a new different place. –> no cues means both memories are competing
reinstatement
recovery of a conditioned behavior that occurs when the individual encounters the US again
Reinstatement experiment
- lebar and Phelps 2005
- participants are shown a blue light then a sound and then just the sound and then tested to just CS to test their fear
- those who got the sound before had more reinstatement
Factors that affect extinction
- number/spacing of trials
- repetition of test cycles
- conducting extinction in multiple contexts
- reminder cues
- compounding extinction stimuli
- delay vs immediate
Number of extinction trials
- with more tirals there is better extinction
spacing of trials
- massed trials produced faster extinction but has more recovery than soaced trials
- spaced are better for therapies
Repetition of test cycles
- more repetitions will lead to more extinction
ex: rats that are tested 8 times a day, the rate of spontaneous recovery decreases
effects of conducting extinction in multiple contexts
training in several different contexts can increase extinction
effect of reminder cues
presenting cues that were present during extinction trainin enhance extinction performance
effect of compounding extinction stimuli
- compounding two extinction stimuli together will deepen the extinction
compounding extinction experiment
- rescorla 2006
- condition three separate CS. extinguish 2 together and the will combine their sub-threshold and be less extinguished. but when tested alone, little recovery because it is deepened
effects of delayed vs immediate extinction
- delayed will have slower extinction but it will be longer lasting than immediate because of memory consolidation
