INTRODUCTION: The central amygdala (CeA) is a key structure in the brain's motivational system, playing a crucial role in processing social behaviors. However, the specific contributions of different neuronal populations to social stimuli processing in CeA remain poorly understood. A deeper understanding of how distinct cell types within the CeA respond to social interactions, as well as their connectivity with other brain regions, is essential for uncovering the neural circuits underlying social behavior. Such insights could provide valuable information for understanding social deficits associated with neuropsychiatric disorders and identifying potential therapeutic targets.

AIM(S): In this study, we aimed to characterize how distinct CeA neuronal populations contribute to processing social stimuli.

METHOD(S): We focused on two well-characterized inhibitory neuron types: somatostatin-positive (SOM) and corticotropin-releasing factor-positive (CRF) neurons. To investigate their functional connectivity, we mapped both the input and output projections of these populations using transgenic SOM-Cre and CRF-Cre mouse models. Stereotactic surgeries were performed to introduce AAV DIO-mCherry for tracing output projections and rabies viruses for input mapping. Following recovery, mice were exposed to social stimuli, and neuronal activation was assessed by mapping cFOS-positive cells.

RESULTS: Our findings provide a detailed characterization of the input and output projections of SOM and CRF neurons in the CeA and their engagement during social stimuli processing. By linking neuronal activation patterns with anatomical connectivity, we identified key circuits involved in social behavior.

CONCLUSIONS: This study advances our understanding of the CeA’s role in social information processing and lays the groundwork for future research into social deficits observed in conditions such as autism spectrum disorder and social anxiety.

FINANCIAL SUPPORT: 2022/47/B/NZ4/01192