Dataset: Fear learning induces synaptic potentiation between engram neurons in the rat lateral amygdala

The lateral amygdala (LA) encodes fear memories by potentiating sensory inputs associated with threats and, in the process, recruits 10-30% of its neurons per memory engram. However, how the network within the LA processes this information, and whether it also plays a role in storing it, is still largely unknown. Using ex vivo 12 patch clamp and in-vivo 32 electrode electrophysiological recordings, in combination with activity-dependent fluorescent and optogenetic tagging and recall, we identified between principal LA neurons in rats a sparsely connected network that is organized in clusters and in which connections between recruited neurons specifically potentiate after fear learning. Our findings of synaptic plasticity in an auto-associative excitatory network of the LA suggest a basic cortical principle through which a small number of pyramidal neurons could encode a large number of memories.