Chapter 9 – Extinction of Conditioned Behavior • Outline – Effects of Extinction Procedures • Decreased responding • Increased variability in responding – Extinction of Original Learning • Spontaneous Recovery • Renewal of Original Excitatory Conditioning • Reinstatement of Conditioned excitation – Enhancing Extinction • Number and Spacing of Extinction Trials • Reducing Spontaneous Recovery • Reducing Renewal • Compounding Extinction Stimuli – What is learned in Extinction • Paradoxical Reward Effects • Mechanisms of the Partial-Reinforcement Extinction Effect
29
Embed
Chapter 9 – Extinction of Conditioned Behavior Outline –Effects of Extinction Procedures Decreased responding Increased variability in responding –Extinction.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Chapter 9 – Extinction of Conditioned Behavior
• Outline – Effects of Extinction Procedures
• Decreased responding• Increased variability in responding
– Extinction of Original Learning• Spontaneous Recovery• Renewal of Original Excitatory Conditioning• Reinstatement of Conditioned excitation
– Enhancing Extinction• Number and Spacing of Extinction Trials• Reducing Spontaneous Recovery• Reducing Renewal• Compounding Extinction Stimuli
– What is learned in Extinction• Paradoxical Reward Effects• Mechanisms of the Partial-Reinforcement Extinction Effect
• So far we have focused on acquisition effects.– What happens when a stimulus predicts the presence of some
outcome• This chapter focuses on what happens when that outcome
is later omitted• Pavlovian
– Acquisition• CS-US
– Extinction• CS alone
• Instrumental– Acquisition
• S+– Barpress/keypeck RF
– Extinction• Barpress/keypeck no longer RF
• Extinction is a hot area of research– Particularly relevant to therapy
• Exposure therapies for phobias– Extinguish fear
• Also for drug addictions– Extinguish cues for drug taking behavior
• Effects of Extinction Procedures– Domjan’s key example
• Key no longer works for door– What do you do?
» Try several times» Try it in a variety of ways
» Jiggle it» Eventually quit
• Effects of Extinction– Decrease in responding– Increase in variability of responding
• Empirical Evidence– Neuringer, Kornell, and Olufs (2001)– Right lever(R), left lever (L), key (K)
• Three responses required• Group Var
– Not allowed to repeat
• Yoked control– No variability requirement but RF was yoked to Group
Var
Variability
Responding
Train Extinction
Var
control
control
Var
• Extinction also can cause a strong emotional response– Frustration (possible aggression)
• Car won’t start• Vending machine doesn’t work• Pigeon’s out of food
• Pigeon’s key pecking with restrained partner– Extinction = attack
• Extinction and Original Learning– Does extinction erase original learning
• Evidence says no– From several lines
» Spontaneous Recovery» Renewal» Reinstatement» Retention of knowledge of the Reinforcer
• Spontaneous Recovery– Phase 1
• acquisition– Train CS-US
– Phase 2 • extinction
– CS alone
– Phase 3• Time off
– Phase 4• Extinction
• What does Spontaneous recovery tell us about extinction learning?– Original learning remains
• A little time off?– Responding returns
• Renewal– A shift in context can renew extinguished learning
• bring back responding
– Demonstrated by Bouton and King (1983) • used the conditioned suppression procedure.
• Phase 1– Train all rats to bar press
• Phase 2
– Train conditioned emotional response to a CS (tone)• CS (tone) US (shock)
• Phase 3 (Extinction)– 3 Groups
• Group Ext A) – Extinguish CER same context as phase 1 and 2
» Present CS alone in same context
• Group Ext B) – Extinguish CER different context
» Present CS alone in different context
• Group NE – No extinction
• Test– Conditioned suppression to tone in original context
• Result– Ext A?
• No Fear
– Ext B?• Fear
– NE?• Most Fear
• Which group demonstrated Renewal?• What does this say about Extinction?
– 1) Initial learning is not forgotten– 2) Extinction is at least somewhat context
specific• Has implications for therapists attempting
to extinguish unwanted behaviors– Extinction of phobia or drug taking behavior
may be specific to the therapists office– Extinction in multiple contexts?
• Reinstatement– Exposure to the US serves as a reminder
• reinstates an extinguished response.
• Train – CS (tone) US (shock) – tone elicits fear.
• Extinction– CS alone.
• Reinstatement– US alone
• Test– Fear tone?
• Yes = reinstatement
• Like Renewal, Reinstatement is context specific– US exposure works best if in the same context
• Reinstatement is also an issue for therapists– Worry that extinguished fears/behaviors will
return if exposed to certain reminder stimuli• Patient has intimacy issues because of abusive
parents– Treated with therapy
• Abusive encounter later in life– Reinstates intimacy issues?
• Enhancing Extinction– Because Extinction can be so useful
therapeutically,efforts have been made to enhance it
• Number and Spacing of Extinction of Trials– More extinction is more effective
• Makes sense– New learning after all
– Massed trials are more effective than spaced trials• This effect seems to be temporary
– Within session effect» Large spontaneous recovery