English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Gating by induced A-Gamma asynchrony in selective attention

MPS-Authors
/persons/resource/persons195711

Hervais-Adelman,  Alexis
Brain and Language Lab, Department of Clinical Neuroscience, University of Geneva;
Neurobiology of Language Department, MPI for Psycholinguistics, Max Planck Society;

External Ressource
No external resources are shared
Fulltext (public)
Supplementary Material (public)
There is no public supplementary material available
Citation

Pascucci, D., Hervais-Adelman, A., & Plomp, G. (2018). Gating by induced A-Gamma asynchrony in selective attention. Human Brain Mapping, 39(10), 3854-3870. doi:10.1002/hbm.24216.


Cite as: http://hdl.handle.net/21.11116/0000-0002-5A21-4
Abstract
Visual selective attention operates through top–down mechanisms of signal enhancement and suppression, mediated by a-band oscillations. The effects of such top–down signals on local processing in primary visual cortex (V1) remain poorly understood. In this work, we characterize the interplay between large-s cale interactions and local activity changes in V1 that orchestrat es selective attention, using Granger-causality and phase-amplitude coupling (PAC) analysis of EEG source signals. The task required participants to either attend to or ignore oriented gratings. Results from time-varying, directed connectivity analysis revealed frequency-specific effects of attentional selection: bottom–up g-band influences from visual areas increased rapidly in response to attended stimuli while distributed top–down a-band influences originated from parietal cortex in response to ignored stimuli. Importantly, the results revealed a critical interplay between top–down parietal signals and a–g PAC in visual areas. Parietal a-band influences disrupted the a–g coupling in visual cortex, which in turn reduced the amount of g-band outflow from visual area s. Our results are a first demon stration of how directed interactions affect cross-frequency coupling in downstream areas depending on task demands. These findings suggest that parietal cortex realizes selective attention by disrupting cross-frequency coupling at target regions, which prevents them from propagating task-irrelevant information.