PARTIAL REINFORCEMENT OF A CONDITIONED EMOTIONAL RESPONSE IN RATS

Conditioned suppression of 32 naive male hooded rats' bar pressing was more resistant to extinction following intermittent reinforcement of a CS than following consistent reinforcement. This effect was obtained whether or not bar pressing was permitted during conditioning as well as during extinction. The effect was amplified by interpolating a large block of nonreinforced trials early in the partial schedule; it was eliminated by adding more reinforced trials prior to the partial schedule. The effect was not obtained by interpolating a large block of nonreinforcements in a continuous schedule. Results were related to instrumental partial reinforcement findings. (20 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.