In order to establish patterns of oscillatory power changes following presentation of the visual grating, gamma-band (40–60 Hz), and alpha-band power (8–13 Hz) were localized for a 300–1,500 ms period post-stimulus presentation. Results for the gamma-band (Figure 3A), show an increase in oscillatory power which localizes to the ventral occipital cortex (Hoogenboom et al., 2006). Results for the alpha band (Figure 3B) showed a general decrease in power, located primarily in occipital areas, but extending into temporal and parietal regions. The more widespread spatial pattern could reflect on-going upstream processes triggered by the appearance of the grating, for example anticipation of the upcoming target (Stenner et al., 2014).
