Lever holding behavior during a leverlift shock escape procedure

Rats were trained either to press a lever or to lift a lever in order to escape shock. Although there were no appreciable differences between escape latencies, the leverlift condition eliminated virtually all of the intertrial lever holding observed under the leverpress condition. While stable escape behavior can be obtained using either the press or lift responses, the use of a leverlift requirement allows for the separate observation of lever holding and freezing, a species-specific defense reaction.