Input-dependent modulation of MEG gamma oscillations reflects gain control in the visual cortex.

ABSTRACT: Gamma-band oscillations arise from the interplay between neural excitation (E) and inhibition (I) and may provide a non-invasive window into the state of cortical circuitry. A bell-shaped modulation of gamma response power by increasing the intensity of sensory input was observed in animals and is thought to reflect neural gain control. Here we sought to find a similar input-output relationship in humans with MEG via modulating the intensity of a visual stimulation by changing the velocity/temporal-frequency of visual motion. In the first experiment, adult participants observed static and moving gratings. The frequency of the MEG gamma response monotonically increased with motion velocity whereas power followed a bell-shape. In the second experiment, on a large group of children and adults

SUBMITTER: Orekhova EV 

PROVIDER: S-EPMC5981429 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature