Temporal coding organized by coupled alpha and gamma oscillations prioritize visual processing

• Complex visual scenes are converted to a temporal code: a ‘to-do list’.
• The order of the temporal code is determined by bottom-up and top-down drives.
• Phase-coding organized by alpha oscillations coordinates competing representations.
• Gamma activity phase-coupled to alpha oscillations segments competing representations.

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.