Prefrontal neuronal circuits of contextual fear conditioning

Abstract

Over the past years, numerous studies have provided a clear understanding of the neuronal circuits and mechanisms involved in the formation, expression and extinction phases of conditioned cued fear memories. Yet, despite a strong clinical interest, a detailed understanding of these memory phases for contextual fear memories is still missing. Besides the well-known role of the hippocampus in encoding contextual fear behavior, growing evidence indicates that specific regions of the medial prefrontal cortex differentially regulate contextual fear acquisition and storage in both animals and humans that ultimately leads to expression of contextual fear memories. In this review, we provide a detailed description of the recent literature on the role of distinct prefrontal subregions in contextual fear behavior and provide a working model of the neuronal circuits involved in the acquisition, expression and generalization of contextual fear memories.

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“…Convergent evidence indicates the brain areas that are dysfunctional in PTSD patients correspond to those responsible for learned fear processing in laboratory animals (Pitman et al, 2012;Maren et al, 2013;Rozeske et al, 2015;Besnard and Sahay, 2016).…”

Selective post-training time window for memory consolidation interference of cannabidiol into the prefrontal cortex: Reduced dopaminergic modulation and immediate gene expression in limbic circuits

“…This implicates the inhibition of neuronal activity in some cortical targets in the impairment of long-term aversive memory. Neuronal tracing studies have shown that the PFC reciprocally projects to the BLA (Hu¨bner et al, 2014) and midline thalamus (Vertes and Hoover, 2008;Varela et al, 2014;Rozeske et al, 2015). Besides, the PFC can indirectly modulate hippocampus activity through its efferences to the nucleus reuniens of the midline thalamus, which directly projects to CA1 (Varela et al, 2014).…”