Avoidance Learning Flashcards
What is passive avoidance?
Must withhold a response (don’t do this or else)
- Exploits natural tendency of MICE to enter dark environments
- Unidirectional – mouse goes from light to dark chamber
What is active avoidance?
Must make a response (do this or else)
- Learns to avoid shock based upon presentation of a light cue
- Unidirectional – mouse is always shocked in the same chamber/location
What is shuttle avoidance?
Actively avoids, no one chamber is safe
- Learns to avoid shock based upon light cue which is dependent upon location of the mouse in the apparatus
- Bi-directional – mouse learns to monitor for cues in both chambers that predict shock
Theory 1: Classical conditioning - Bolles (1971)
Species-specific defence reactions (SSDRs) e.g., flight and freezing (Bolles, 1971)
By classical conditioning animals learn to respond to stimuli associated with pain
SSDR of flight good basis for active avoidance, freezing for passive avoidance
CRs like URs are expected on the basis of stimulus substitution
- Stimulus substitution – where CR resembles UR
Avoidance responses like the SSDR (e.g. running away) are much more easily learned
Model of fear and pain - Bolles and Fanselow (1980)
Fear can potentiate a variety of SSDRs and can inhibit other motivational systems, including pain
The fear and pain systems are functionally organised to allow an animal to defend itself and recover from attack
Why are some avoidance behaviours easier to learn?
Running is far easier to learn than turning or standing in order to avoid receiving an electric shock in running wheel
This is because running is a SSDR – much easier to learn as natural response
What are some issues with the theory of classical conditioning regarding avoidance learning?
It is difficult, but possible, to train animals to perform avoidance responses that do not resemble any SSDR
Avoidance learning is faster when the designated response causes omission of the aversive US than it is in a group exposed only to a classical contingency – can’t all be classical because learning is better when you add an instrumental component
After just a couple of signalled shocks, an animal may respond so efficiently to the CS that it never gets another shock – why doesn’t the conditioned fear extinguish?
What does the two factor theory add to classical conditioning?
Includes idea that reducing exposure to the classically conditioned warning signals is also reinforcing
In active avoidance animals also learn instrumentally, to escape the (secondarily aversive) stimuli that warn shock is imminent
Adaptive anticipation: motivated to reduce fear, better to escape sight rather than fangs of tiger
What are the two factors in the two factor theory?
Pavlovian fear conditioning
Reinforcement through fear reduction
