SOM-IN ⁺ inputs are distributed similarly in adult brain and organotypic slices. (a) SOM-IN presynaptic boutons, identified in SOM^Cre/+:R26^tdTom/+ adult mice as SOM-tdTomato⁺VGAT⁺ terminals, are denser in upper cortical layers of brain and organotypic slices. Scale bars, 10 μm. (b) Fraction of VGAT⁺ puncta colocalized to SOM-tdTomato⁺ boutons. Of note, the majority of VGAT⁺ puncta in adult brain and organotypic slices cortical L1 are SOM-IN inputs. Adult brain: n = 31 (L1) and 33 (L5) FOVs from three SOM^Cre/+:R26^tdTom/+ mice. Organotypic slices: n = 24 (L1), 12 (L5) FOVs from 1 SOM^Cre/+:R26^tdTom/+ culture. Results are presented as minimum to maximum box plots.