A role for GABAergic interneuron diversity in circuit development and plasticity of the neonatal cerebral cortex

•Interneuron diversity is established at the moment of neurogenesis.•All interneuron subtypes contribute to early neonatal circuit formation.•The interaction between interneuron subtypes is likely important for plasticity.•These early interneuron circuits can be distinct from those present in adults.

GABAergic interneurons are a highly heterogeneous group of cells that are critical for the mature function and development of the neocortex. In terms of the latter, much attention has focused on the well-established role of parvalbumin (PV+)-expressing, fast spiking, basket cells in determining the critical period plasticity. However recent endeavours have started to shed the light on the contribution of other interneuron subtypes to early circuit formation and plasticity. Data suggests that there are significant interactions between PV+ cells and other interneuron subtypes that regulate circuit development in rodents in the first postnatal week. Moreover, a number of these early interactions are transient which points to an important, distinct role for interneuron diversity in setting up emergent neocortical processing.