No effect of partial reinforcement on fear extinction learning and memory in C57BL/6J mice.

Partial reinforcement schedules, wherein a conditioned stimulus (CS) is intermittently paired with an unconditioned stimulus (US) during associative learning, have been widely studied and found to affect the extinction and recall of learned behaviors. Notably, behaviors conditioned under partial (as opposed to consistent) reinforcement are more resistant to extinction, an effect known as the partial reinforcement extinction effect (PREE). The present study initially aimed to examine the effects of partial reinforcement on the acquisition and recall of fear extinction (FE) when altering the contextual environment.