title: Layer-specific entrainment of γ-band neural activity by the α rhythm in monkey visual cortex.
abstract: Although the mammalian neocortex has a clear laminar organization, layer-specific neuronal computations remain to be uncovered. Several studies suggest that gamma band activity in primary visual cortex (V1) is produced in granular and superficial layers and is associated with the processing of visual input. Oscillatory alpha band activity in deeper layers has been proposed to modulate neuronal excitability associated with changes in arousal and cognitive factors. To investigate the layer-specific interplay between these two phenomena, we characterized the coupling between alpha and gamma band activity of the local field potential in V1 of the awake macaque. Using multicontact laminar electrodes to measure spontaneous signals simultaneously from all layers of V1, we found a robust coupling between alpha phase in the deeper layers and gamma amplitude in granular and superficial layers. Moreover, the power in the two frequency bands was anticorrelated. Taken together, these findings demonstrate robust interlaminar cross-frequency coupling in the visual cortex, supporting the view that neuronal activity in the alpha frequency range phasically modulates processing in the cortical microcircuit in a top-down manner.
authors.affiliation: Donders Institute for Brain, Cognition, and Behaviour, Radboud University Nijmegen, 6500 HE Nijmegen, The Netherlands.
authors.forename: Eelke
authors.initials: E
authors.lastname: Spaak
authors.forename: Mathilde
authors.initials: M
authors.lastname: Bonnefond
authors.forename: Alexander
authors.initials: A
authors.lastname: Maier
authors.forename: David A
authors.initials: DA
authors.lastname: Leopold
authors.forename: Ole
authors.initials: O
authors.lastname: Jensen
mesh_terms: D000818:Animals; D004566:Electrodes; D000882:Haplorhini / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D014793:Visual Cortex / Q000166:cytology / Q000502:physiology*