Two distinct projection pathways converge onto the same BLA neurons to contribute to fear memory retrieval

Studying the neural circuits that mediate context-induced fear memory retrieval is of importance to develop new therapeutic approaches to prevent post-traumatic stress disorder relapse. The basolateral amygdala (BLA) is crucial for context-induced retrieval of fear memory. Previous studies indicate that projection neurons from the ventral hippocampus CA1 (vCA1) to the BLA (vCA1-BLA neurons) mediate context-induced retrieval of fear memory.

However, it remains unclear whether other projection neurons to the BLA are involved in context-induced retrieval of fear memory and how they interact with vCA1-BLA neurons. Our findings indicate that the postrhinal cortex (POR) to the BLA (POR-BLA) neurons are also involved in context-induced retrieval of fear memory. These neurons innervate the same BLA neurons as vCA1-BLA neurons and participate in fear memory retrieval.

These results suggest that two different projection neurons of POR-BLA and vCA1-BLA innervate on the same BLA neurons and POR-BLA neurons and vCA1-BLA neuron contribute to fear memory retrieval. These findings provide new insights into the neural mechanisms underlying fear memory retrieval. This is a preview of subscription content, access via your institution Receive 12 print issues and online access Prices may be subject to local taxes which are calculated during checkout Primary data in the results reported in this study are available after publication from the corresponding reasonable written request.

Chaaya N, Battle AR, Johnson LR. An update on contextual fear memory mechanisms: transition between amygdala and hippocampus. Neurosci Biobehav Rev. 2018;92:43–54.

Lotfinia S, Afshar A, Yaseri A, Olff M, Quidé Y. Functional brain changes after alternative pharmacological interventions in posttraumatic stress disorder: A systematic review of clinical trials. Brain Behav. 2023;13:e3292.

Article CAS PubMed PubMed Central Google Scholar Li HP, Cheng HL, Ding K, Zhang Y, Gao F, Zhu G, et al. New recognition of the heart-brain axis and its implication in the pathogenesis and treatment of PTSD. Eur J Neurosci. 2024;60:4661–83.