Lecture 15: Extinction

Question 1

What is the effect of extinction procedures?

Answer 1

• A decline in responding only following an established Pavlovian or Instrumental association

Question 2

What is omitted in extinction procedures?

Answer 2

• US or reinforcer

Question 3

Does extinction cause a reversal of learning?

Answer 3

No, true reversal is nearly impossible

Question 4

What does extinction of pavlovian/associative/classical responding look like?

Answer 4

• Presentations of CS without the US
• Multiple presentations are almost always necessary in spite of rapidity of some forms of fear conditioning
• Results in reduced responding

Question 5

What does extinction of operant conditioning look like?

Answer 5

• No longer provide outcome (ex. reinforcer) in response to behaviour
• Extinction is opposite to learning/training
• Learn that reinforcer is omitted, do not work as hard for it

Question 6

Why is extinction important or even necessary?

Answer 6

• Promote adjustments to behaviour in response to changing environments
• Not many reinforcement schedules remain in effect forever
• Ex. children are praised for drawing crude representation of people in nursery school, not rewarded in high school
• Without adaptation, may not get reinforcer you need/want

Question 7

What is extinction?

Answer 7

• Active process produced by unexpected absence of reinforcer
• Not erasing previous learning
• New type of S-R association

Question 8

What is forgetting?

Answer 8

• Passage of time
• Does not require non-reinforced encounters with CS or CR
• Not manipulating or omitting US/reinforcer

Question 9

What is exposure therapy?

Answer 9

• An extinction procedure where participants are exposed to cues that elicit fear in the absence of the aversive US
• Helps with pathological fears/phobias and drug addiction
• Ex. think about snakes in a safe space; exposure to cues related to drug use to extinguish craving

Question 10

What are virtual reality techniques used for?

Answer 10

• Allow for more vivid realistic exposure to fearful stimuli when its not possible/ethical to actually expose them to the stimuli
• Ex. PTSD

Question 11

What are the 2 basic behavioural effects of extinction?

Answer 11

• Target response decreases when response no longer results in reinforcement
• Extinction increases response variability, at least at first

Question 12

What did Neuringer, Kornell and Olufs discover?

Answer 12

• 3 different responses leads to reinforcer
• Group Var: had to make unique order of responses
• Group Yoke: no requirement to vary key responses
• Variability increased with extinction
• Extinction produced decrease in rate of responding

Question 13

What is frustration?

Answer 13

• The emotional reaction induced by withdrawal of an expected reinforcer
• Need previous learning history
  Ex. attacks other pigeon when reinforcer is withheld
• This is a problem in exposure therapy (can lead to aggression)
  Ex. kick vending machine when you do not receive food

Question 14

What is consolidation?

Answer 14

• Retrieval from different long-term memory

- Requires protein synthesis

Question 15

What happens when anisomycin (which blocks protein synthesis) is added in a memory test?

Answer 15

• No consolidation of pairings
• Not necessarily due to extinction, but could not properly reconsolidate memory
• Need to retrieve memory to form CR

Question 16

What are 4 things that prove that extinction does not erase original learning?

Answer 16

• Spontaneous recovery
• Renewal
• Reinstatement
• Retention of knowledge of reinforcer

Question 17

What is spontaneous recovery?

Answer 17

• Behaviour returns after extinction

- 8 day rest period in between

Question 18

What is renewal of original excitatory conditioning?

Answer 18

• Recovery of acquisition performance
• Contextual cues change during extinction
• Previous experience or neutral labs
• New context disrupts retrieval of memory (fear memory generalizes with acquisition, not extinction)

Question 19

What is reinstatement of conditioned excitation?

Answer 19

• Different context leads to the same response

- Increase in behaviour with the same (original) context

Question 20

Why does context matter?

Answer 20

• Context conditioning and summation of excitation (might cause reinstatement)
• Context helps disambiguate the significance of a stimulus that has a mixed history of conditioning and excitation (mixed history leads to more effect of context)
• Conditioning of cues in situation summate with excitation remaining at end

Question 21

What happens with a mixed history and a change in context?

Answer 21

• Don’t freeze as much
• Initial memory is not as strong
• Contextual cues gain excitatory properties with acquisition

Question 22

What is retention of knowledge of reinforcer?

Answer 22

• Devaluation should lead to decrease in responding

- Behaviour changes, but the associations are maintained

Question 23

What are some 7 strategies for enhancing extinction?

Answer 23

• Increase number of extinction trials
• Massed = faster extinction, spaced = stronger extinction
• Immediate = faster extinction, delayed = stronger extinction
• Repeated extinction sessions
• Extinction in multiple contexts
• Present retrieval cues for extinction during test
• Compound extinction

Question 24

What effect does compounding extinction stimuli have?

Answer 24

• Deepens extinction of stimulus greater than the stimulus that underwent extinction alone

Question 25

How does previous manipulation affect extinction?

Answer 25

• May take longer to learn extinction

- Ex. Experience with nicotine may lead rats to respond more even without reinforcer