Role of the ventral medial prefrontal cortex in mediating behavioral control-induced reduction of later conditioned fear.

A prior experience of behavioral control over a stressor interferes with subsequent Pavlovian fear conditioning, and this effect is dependent on the activation of the ventral medial prefrontal cortex (mPFCv) at the time of the initial experience with control. It is unknown whether mPFCv activity is necessary during fear learning and/or testing for this interference to occur. One week following controllable stress, the infralimbic cortex (IL) was temporarily inactivated either before fear learning or later testing. Inactivation of the IL before the test for conditioned fear, but not before conditioning, blocked the fear reducing effects of prior controllable stress. This suggests that the experience with control interferes with the expression of fear behavior and not the learning of the association, and that the mPFCv is needed to regulate conditioned fear behavior.