Within the visual system, there is strong evidence for a dynamic coupling between alpha phase (8–13 Hz) and gamma amplitude (>40 Hz; Voytek et al., 2010; Spaak et al., 2012; Bonnefond and Jensen, 2015). Alpha oscillations are associated with pulses of cortical inhibition every ~100 ms (Jensen and Mazaheri, 2010; Klimesch, 2012), whilst supporting communication through phase dynamics (Fries, 2015). In contrast, gamma oscillations emerge through local excitatory and inhibitory interactions, and synchronize local patterns of cortical activity (Singer and Gray, 1995; Buzsáki and Wang, 2012). In visual cortex, ongoing gamma-band activity becomes temporally segmented by distinct phases of alpha-band activity (Spaak et al., 2012; Bonnefond et al., 2017), possibly via inter-laminar coupling between supragranular and infragranular cortical layers (Mejias et al., 2016). Intriguingly, this coupling has been proposed to act as a mechanism for the dynamic co-ordination of brain activity over multiple spatial scales, with high-frequency activity within local ensembles coupled to large-scale patterns of low-frequency phase synchrony (Bonnefond et al., 2017), both within the visual system (Bonnefond and Jensen, 2015), and more widespread neurocognitive networks (Florin and Baillet,
