Exploring How mPFC and Hippocampus Enhance Generalization in PTSD-like Behavior Model

Post Traumatic Stress Disorder (PTSD) patients often show excessive fear generalization to harmless cues. Animal model studies illustrate that, hippocampus and medial prefrontal cortex (mPFC) play important roles in the process of discrimination and generalization of fear memories: as the hippocampus maintain the accuracy of memory through pattern separation and neurogenic mechanisms, mPFC regulates the separation of fear and safe stimuli via the neuroplasticity mechanism mediated by excitatory NMDA receptors. mPFC and hippocampus coordinate emotional valence through the hippocampus-amygdala circuit, achieving the remote updating of memories. If the reconsolidation process of the hippocampus of mPFCs regulation function are unbalanced, the fear memory would remain coarse cortical representation, which increases memory generalization. Understanding these mechanisms would be useful to help conduct the targeted intervention of PTSD, such as promoting the forgetting of the traumatic memories through enhancing the neurogenesis in the hippocampus, and improving the recognition of fear cues through regulating mPFC networks, which could help undermine the symptom of excessive generalization.