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Theta activity paradoxically boosts gamma and ripple frequency sensitivity in prefrontal interneurons.

ABSTRACT: Fast oscillations in cortical circuits critically depend on GABAergic interneurons. Which interneuron types and populations can drive different cortical rhythms, however, remains unresolved and may depend on brain state. Here, we measured the sensitivity of different GABAergic interneurons in prefrontal cortex under conditions mimicking distinct brain states. While fast-spiking neurons always exhibited a wide bandwidth of around 400 Hz, the response properties of spike-frequency adapting interneurons switched with the background input's statistics. Slowly fluctuating background activity, as typical for sleep or quiet wakefulness, dramatically boosted the neurons' sensitivity to gamma and ripple frequencies. We developed a time-resolved dynamic gain analysis and revealed rapid sensitivity modulations that enable neurons to periodically boost gamma oscillations and ripples during specific phases of ongoing low-frequency oscillations. This mechanism predicts these prefrontal interneurons to be exquisitely sensitive to high-frequency ripples, especially during brain states characterized by slow rhythms, and to contribute substantially to theta-gamma cross-frequency coupling.

SUBMITTER: Merino RM

PROVIDER: S-EPMC8713793 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Theta activity paradoxically boosts gamma and ripple frequency sensitivity in prefrontal interneurons.

Merino Ricardo Martins RM Leon-Pinzon Carolina C Stühmer Walter W Möck Martin M Staiger Jochen F JF Wolf Fred F Neef Andreas A

Proceedings of the National Academy of Sciences of the United States of America 20211201 51

Fast oscillations in cortical circuits critically depend on GABAergic interneurons. Which interneuron types and populations can drive different cortical rhythms, however, remains unresolved and may depend on brain state. Here, we measured the sensitivity of different GABAergic interneurons in prefrontal cortex under conditions mimicking distinct brain states. While fast-spiking neurons always exhibited a wide bandwidth of around 400 Hz, the response properties of spike-frequency adapting interne ...[more]

PMID: 34903668

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Theta activity paradoxically boosts gamma and ripple frequency sensitivity in prefrontal interneurons.

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Theta activity paradoxically boosts gamma and ripple frequency sensitivity in prefrontal interneurons.

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