The Opportunity for Aggression as an Operant Reinforcer During Aversive Stimulation1

Squirrel monkeys were provided with a chain-pulling response which produced an inanimate object that could be attacked. In the absence of pain-shock, little or no chain-pulling occurred. When pain-shocks were delivered, chain-pulling responses increased. The chain-pulling response was successively reinforced, extinguished, reinforced, and again extinguished by presenting or withdrawing the opportunity to attack as the reinforcing event. Aggression appears to be a distinctive motivational state which is produced by aversive stimulation and which can be used to condition and maintain new behavior.