Aversive Conditioning

Reinforcement Punishment

Positive contingency

Negative contingency

Chocolate Bar Electric Shock

Excused from Chores

No TV privileges – omission training

Effect on Behavior

(passive avoidance)

(active avoidance)

Some potential problems with punishment

• Moral issues

• Side effects

• Only shows subject what NOT to do.

• Timing of punishment

Punishment on a VR schedule

Cumulative record of pecking in birds Pecking reinforced on a VI 3-min schedulePecking punished on a FR schedule

When there is a discriminative stimulus for punishment

Student #1

Student #2

Sreward Only Sreward & Spunishment

Negative reinforcement – Active Avoidance

Negative Reinforcement - Escape

Avoidance: Experimental Paradigm

The shuttle box

Light = CS

Light Shock

Shuttling stops shock

Two-Process Theory of Avoidance

Light Shock ( = Pavlovian Conditioning)

-Light elicits fear

Shuttling Reduction of Fear (= negative reinforcement)

Is the termination of a shock-associated CS reinforcing?

Pavlovian Conditioning

ToneShock

Phase 1 Phase2

Escape (no shocks)

Shuttling turns off Tone

Fear in Active Avoidance

Phase 1 Phase 2

Active avoidance training

Does avoidance CS suppress lever pressing?

Fear of the CS declines with extensive avoidance training

Two-Process Theory of Avoidance

Light Shock ( = Pavlovian Conditioning)

-Light elicits fear

Shuttling Reduction of Fear (= negative reinforcement)

What should happen with extensive training?

Learned Helplessness Paradigm“Triadic” Design

Group A: Escapable Shock

Group B: Yoked Inescapable Shock

Group C: Exposure to apparatus only

Phase 1 Phase 2

Escape/Avoidance training

(For Group A shock can be terminated by rotating a wheel.)

Phase 2 Results

Inescapable shock

escapable shock

Possible Explanations• Learned Helplessness: Organisms learn that their

behavior is ineffectual

• Poverty of activity: inescapable shock reduces the variability in behavior that is so crucial for operant conditioning

• Inattention: animals stop attending to their own behavior

Effects of Marking

Inescapable shock

escapable shock

Marking group

Learned Helplessness in the Spinal Cord?

Grau and Colleagues

Operant Procedure: Shock administered whenever leg is extended. Spinal cord learns to keep leg flexed to avoid shock.

Learned Helplessness: Experience of uncontrollable legshock (yoked group) prevents subsequent avoidance learning with controllable shock

LH in Humans

LH produced by…

insoluble math or logic problems

living in a crowded dorm