Background correlations selectively boost the gamma-sensitivity of cortical GABAergic neurons

Gamma oscillations in cortical circuits critically depend on GABAergic interneurons. Precisely which interneuron types and populations can drive cortical gamma, however, remains unresolved and may depend on brain state. Here we show that spike-frequency adapting interneurons dramatically boost their gamma-sensitivity in the presence of slowly fluctuating background activity. This mechanism allows the dynamic control of gamma oscillations, induces cross-frequency coupling and predicts these interneurons to be exquisitely sensitive to high-frequency ripples.