Shown is a confocal image of a pre-adolescent mouse cortical brain slice. All cell nuclei are labelled with DAPI (grey). Cyan depicts mRNA coding for Synaptic Ras GTPase activating protein (Syngap1). Syngap1 is expressed in inhibitory parvalbumin-expressing neurons (yellow), with expression peaking in pre-adolescence. Research suggests that mutations in the gene for Syngap1 drive sensory dysfunction and cognitive deficits by impairing excitatory synapse development. But whether Syngap1 mutations impair inhibitory neuro function to hinder sensory processing and cognition is unclear. See the article by Vidya Jadhav et al. for information on how a Syngap1 mutation in inhibitory parvalbumin-expressing neurons impairs auditory sensory processing and cognitive flexibility. Cover image: Graziella Di Cristo