VIP Cortical Interneurons: A Critical Reassessment of the Disinhibition Framework

VIP-expressing GABAergic interneurons account for fewer than one in ten cortical interneurons yet have become the canonical substrate for state-dependent disinhibition, recruited by locomotion, arousal, reward, and top-down attention to suppress somatostatin-positive cells and release pyramidal dendrites from inhibition. This review takes the field’s confidence in that single motif as its starting point and asks what the molecular, developmental, morphological, intrinsic-physiological, synaptic, in-vivo, oscillatory, computational, and translational evidence actually constrains.

Across thirteen sections we synthesise 391 actively cited primary studies (from a closed-allowlist corpus of 1,038 verified DOIs) under blinded actor–critic separation: a structured taxonomy of CGE-derived VIP/CR/CCK molecular subtypes; quantitative comparisons of intrinsic firing across published cohorts; the audited Pfeffer 2013 connectivity matrix and its three documented alternative motifs (direct VIP→PV, VIP→pyramidal, layer-1 VIP→NDNF); cross-area generalisation of the disinhibitory schematic from V1 and auditory cortex to PFC, hippocampus, and somatosensory cortex; and an effect-size meta-analysis showing that VIP→pyramidal disinhibition is robust in locomotion-paired V1 but is not universally observed across published preparations.

Where the literature converges, we mark consensus; where preparations disagree (e.g., Pakan 2016, Dipoppa 2018 on locomotion polarity in higher visual areas), we surface the disagreement explicitly rather than averaging it away. We argue that the disinhibitory framework is best read as a context-dependent tendency — strong in superficial layers of mouse V1 and primary auditory cortex during locomotion-paired stimulation, weaker or absent in deep layers, prefrontal territories, and species other than mouse — and that future computational models should treat it as one of several co-existing motifs rather than a default circuit assumption.

Keywords: VIP interneurons; cortical inhibition; disinhibition; circuit motifs; GABAergic; CGE; somatostatin; locomotion; arousal; computational neuroscience.