PARTIAL NEGATIVE REINFORCEMENT: FIXED‐RATIO ESCAPE

Abstract

Rats were unable to sustain performance when eight bar‐presses turned off shock (—FR 8). In a second experiment, thirsty rats were able to maintain a moderate response rate when performance on —FR 8 was also reinforced with water. Some rats continued to bar‐press on —FR 8 after withdrawal of positive reinforcement, but at a much lower rate. A possible explanation of the results is that during intermittent escape conditioning in a free‐responding situation the absence of shock itself acquires aversive properties.