Two septal-entorhinal GABAergic projections differentially control coding properties of spatially tuned neurons in the medial entorhinal cortex.

Septal parvalbumin-expressing (PV) and calbindin-expressing (CB) projections inhibit low-threshold and fast-spiking interneurons, respectively, in the medial entorhinal cortex (MEC). We investigate how the two inputs control neuronal activity in the MEC in freely moving mice. Stimulation of PV and CB terminals causes disinhibition of spatially tuned MEC neurons, but exerts differential effects on temporal coding and burst firing.