Significant increases in beta ERD amplitude were observed in a widespread network of sensorimotor regions. To the left, an axial image shows areas of the left precentral gyrus, left supplementary motor area, and the right precentral and postcentral gyri where the amplitude of the pre-movement beta ERD increased from 09:00 to 16:00 hours (p < 0.01, cluster-corrected). Significant increases in beta ERD amplitude from 09:00 to 16:00 were also observed in the left premotor cortices (sagittal image). Both images are shown at the same threshold (p < 0.01, cluster-corrected) and in radiological convention. Color scale bar is shown on the far right.