5 - Negative Reinforcement and Avoidance Learning

Reinforcement and Punishment

Escape Learning

• barrier divides shutter box — one half has grid floor

• warning signal (WS) comes on — followed by mild foot shock through grid floor

• subject can escape shock by leaping over barrier to safe area

Avoidance

• animal soon learns to jump over barrier when WS comes on and avoids shock altogether

• escape = turning off some currently occurring aversive effect

• avoid = preventing some aversive event from occurring

2 Process Theory — 1. Conditioned Fear

• assumes that classical conditioning of fear occurs to WS during escape phase

  • WS (pav S) precedes the Shock (O)

  • O produces fear (R)

  • w repeated trials — WS conditioned to generate fear as conditioned response (R)

Avoidance and Fear

• 2 process theory assumes avoidance behaviour is motivated and maintained by fear

• `Kamin study on strength of avoidance behav and level of fear to WS

  • well trained animals showed avoidance but low levels of fear to WS

  • but still some fear

Safety Signals

• successful avoidance produces period of safety

  • cues that signal this period of safety can become safety signals

• safety from aversive outcome is signaled by

  • offset of warning signal

  • stimuli associated w escape

  • avoidance response itself

safety = low prob of aversive outcome

safety signal = cue that predicts absence of aversive outcome

Why are Safety Signals Important

• improve acquisition of avoidance

  • associated with relief

  • act as secondary reinforcers

• maintain avoidance in absence of overt fear

• protect warning signals from extinction

• avoidance does not just remove danger — creates safety

  • safety can become something that org actively seeks

• superstitious avoidance

  • rituals that produce safety signals

Treatment of Avoidance Flooding

• individual avoids the WS — thus reducing fear

• flooding involves forcing the indv to experience the WS

  • step 1 — prevent avoidance response

  • step 2 — extinguish fear to WS

Treatment of Conditioned Fear

Systemic desensitization

Treatments of avoidance

• problems w exposure therapy

  • exposure in the context of therapy obviously different

• pavlovian conditioning (inhibition of fear)

  • therapist acts as safety signal

  • original association w fear is protected

Applications of Avoidance Treatments - Chronic Pain

• fear avoidance model of chronic pain

• avoidance of movement hinders recovery

• prominence of safety signals, safety behaviours

• however — functional assessment needs to be carefully performed

  • some safety behaviours are rational