Fixed-ratio escape reinforcement

Escape responses of squirrel monkeys were reinforced according to a fixed-ratio schedule. The reinforcement was a period of safety from a stimulus that signalled the delivery of intermittent pain-shocks. When the frequency of shock was gradually reduced, the performance remained at a high level until the shocks were quite infrequent. Similarly, the duration of the period of safety could be reduced to a few seconds with little loss of behavior. Thus, the responses appeared to be reinforced by even a brief period of safety, the actual degree of shock reduction being fairly slight. The changes in responding during this fixed-ratio escape procedure were comparable to the response changes typically obtained during fixed-ratio food procedures.     

A comparison of several procedures for eliminating behavior

The pecking response of pigeons was reinforced when a minimum period of time had elapsed since the last response (DRL schedule of food-reinforcement). Punishment, satiation, extinction, and stimulus change were employed separately to reduce responding. When the effects of the four procedures were compared, punishment was found capable of producing a more immediate, complete and long lasting response reduction than the others. Punishment had its maximum effect on the responses that were least relevant to reinforcement. The punishment reduced the frequency of the short inter-response times to a greater extent than did either extinction or satiation. In this way, punishment actually increased the efficiency of the DRL responding.