Entrainment of Neuronal Oscillations as a Mechanism of Attentional Selection

TLDR

Gamma‑band oscillations are clearly integral to visual attention, whereas the role of lower‑frequency oscillations is still debated, despite mounting evidence that they rhythmically shift excitability in local neuronal ensembles. Here, we show that when attended stimuli are in a rhythmic stream, delta‑band oscillations in the primary visual cortex entrain to the rhythm of the stream, resulting in increased response gain for task‑relevant events and decreased reaction times. Hierarchical cross‑frequency coupling causes delta phase to determine momentary power in higher‑frequency activity. These instrumental functions of low‑frequency oscillations support a conceptual framework that integrates numerous earlier findings.

Abstract

Whereas gamma-band neuronal oscillations clearly appear integral to visual attention, the role of lower-frequency oscillations is still being debated. Mounting evidence indicates that a key functional property of these oscillations is the rhythmic shifting of excitability in local neuronal ensembles. Here, we show that when attended stimuli are in a rhythmic stream, delta-band oscillations in the primary visual cortex entrain to the rhythm of the stream, resulting in increased response gain for task-relevant events and decreased reaction times. Because of hierarchical cross-frequency coupling, delta phase also determines momentary power in higher-frequency activity. These instrumental functions of low-frequency oscillations support a conceptual framework that integrates numerous earlier findings.