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PubMed · 12194875

Gain modulation from background synaptic input.

Frances S Chance·L F Abbott·Alex D Reyes
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Abstract

Gain modulation is a prominent feature of neuronal activity recorded in behaving animals, but the mechanism by which it occurs is unknown. By introducing a barrage of excitatory and inhibitory synaptic conductances that mimics conditions encountered in vivo into pyramidal neurons in slices of rat somatosensory cortex, we show that the gain of a neuronal response to excitatory drive can be modulated by varying the level of "background" synaptic input. Simultaneously increasing both excitatory and inhibitory background firing rates in a balanced manner results in a divisive gain modulation of the neuronal response without appreciable signal-independent increases in firing rate or spike-train variability. These results suggest that, within active cortical circuits, the overall level of synaptic input to a neuron acts as a gain control signal that modulates responsiveness to excitatory drive.

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Action PotentialsAnimalsArtifactsElectric StimulationGenetic VariationModels, NeurologicalNeural InhibitionNeural PathwaysNeuronsOrgan Culture TechniquesRatsSomatosensory CortexSynapsesSynaptic TransmissionJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Frances S Chance, L F Abbott, Alex D Reyes. 2002-08-15. Gain modulation from background synaptic input.. https://doi.org/10.1016/s0896-6273(02)00820-6

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