Precise synaptic organization of a memory network

In order to examine how synaptic inputs to individual neurons are organized in a distributed memory network, researchers from the Friedrich group performed electrophysiological recordings in the zebrafish homolog of the olfactory cortex. They found that large excitatory inputs were paired with large inhibitory inputs, which may seem counterintuitive because inhibition cancels excitation. However, theoretical models predicted such a 'precise balance' of synaptic inputs because it stabilizes recurrent networks that store memories. Two antagonistic forces are necessary to build a working nervous system: excitation and inhibition. Excitatory/inhibitory signaling from one cell to the next makes the latter cell more/less likely to fire. The balance between neural excitation and neural inhibition is crucial to healthy cognition and behavior. Insights into the tuning of excitatory and inhibitory inputs to individual neurons will help understand how a neural circuit works.