Autaptic self-inhibition of cortical GABAergic neurons: Synaptic narcissism or useful introspection?

•Specific connectivity patterns between interneurons and excitatory cells.•Cortical disinhibition is necessary for behavioral functions.•Cortical disinhibition is provided by specific interneuron-interneuron connections.•Autaptic self-inhibition of PV cells: a very efficient disinhibition stratagem.•A dual role of autaptic inhibition in temporally coordinating PV basket cells.

Fast synaptic inhibition sculpts all forms of cortical activity by means of a specialized connectivity pattern between highly heterogeneous inhibitory interneurons and principal excitatory cells. Importantly, inhibitory neurons connect also to each other extensively, following a detailed blueprint, and, indeed, specific forms of disinhibition affect important behavioral functions. Here we discuss a peculiar form of cortical disinhibition: the massive autaptic self-inhibition of parvalbumin-(PV) positive basket cells. Despite being described long ago, autaptic inhibition onto PV basket cells is rarely included in cortical circuit diagrams, perhaps because of its still elusive function. We propose here a potential dual role of autaptic feedback inhibition in temporally coordinating PV basket cells during cortical network activity.