recall. At the same time, we saw an enhancement of the GCImPFC→BLA (Figure 8D; p=4.7 × 10−5, MLR), without a corresponding change in the GCIBLA→mPFC (p=.97), suggesting that the observed increase in fast gamma power was the result of enhanced mPFC input to the BLA. These data are consistent with recently reported changes in mPFC-BLA theta directionality during extinction (Lesting et al., 2013), and suggest that the enhancement of synchronous fast gamma oscillations of the mPFC-BLA circuit is a fundamental mechanism for suppression of fear responses during both fear discrimination and extinction.
