Temporal coding organized by coupled alpha and gamma oscillations prioritize visual processing.
Sensory systems must rely on powerful mechanisms for organizing complex information. We propose a framework in which inhibitory alpha oscillations limit and prioritize neuronal processing. At oscillatory peaks, inhibition prevents neuronal firing. As the inhibition ramps down within a cycle, a set of neuronal representations will activate sequentially according to their respective excitability. Both top-down and bottom-up drives determine excitability; in particular, spatial attention is a major top-down influence. On a shorter time scale, fast recurrent inhibition segments representations in slots 10-30 ms apart, generating gamma-band activity at the population level. The proposed mechanism serves to convert spatially distributed representations in early visual regions to a temporal phase code: that is, 'to-do lists' that can be processed sequentially by downstream regions.
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands. Electronic address: ole.jensen@donders.ru.nl.
Ole
O
Jensen
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
Bart
B
Gips
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
Til Ole
TO
Bergmann
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
Mathilde
M
Bonnefond
D000513:Alpha Rhythm / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D004569:Electroencephalography; D065818:Gamma Rhythm / Q000502:physiology*; D006801:Humans; D010775:Photic Stimulation; D014795:Visual Pathways / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*