Amygdala excitability across development: mechanisms, environmental influences, and behavioral outcomes

Recent work in rodent models provides mechanistic insights into how the excitability of principal neurons is dynamically regulated to facilitate the encoding and retrieval of emotionally salient memories in the basolateral amygdala (BLA). In this review, we discuss the physiological mechanisms governing BLA excitability, emphasizing their impact on the recruitment of defined BLA ensembles encoding distinct behavioral states. In addition, we summarize the current understanding of how these mechanisms are established during development and suggest that this may follow distinct developmental phases. Lastly, we outline recent findings on how early-life adversity or genetic risk factors can acutely perturb developmental trajectories and may lead to enduring changes in BLA circuit function, with implications for neurodevelopmental disorders.