Schedule of partial delay of reinforcement and resistance to extinction.

Abstract
In 3 groups of 12 rats each, resistance to extinction on the runway was greatest following 27 partial delay acquistion trials in which delayed and immediate reinforcement alternated, next greatest following random partial delay, and least following immediate reinforcement on all trials. It was suggested that following a small number of partial delay acquisition trials, resistance to extinction is regulated to an extensive extent by number of transitions from delayed trials to immediate trials. Certain similarities in extinction findings between partial delay and partial reinforcement were discussed.