Fig. 4
From: Mu rhythm motor–auditory delay in imagined speech mirrors overt speech timing
Source space power decrease time course in beta-band frontal regions and alpha-band temporal regions. (a) The red colored area delimited by black contours represents frontal regions which most prominently show the beta power decrease across participants. (b) The blue colored area delimited by black contours represents temporal regions which most prominently show the alpha power decrease across participants. (c) The average across source space vertices of the baseline normalized envelopes extracted from the frontal beta (red) and temporal alpha (blue) clusters are represented. The solid lines represent the mean and the shaded area surrounding the solid lines represent the standard error of the mean. The vertical dashed black line represents the expected speech onset measured in the behavioral pretest. The colored stars and vertical dashed lines represent the smallest frontal beta (red) and temporal alpha (blue) ERD onsets. (d) The distribution of individual subjects’ frontal beta and temporal alpha ERD onsets are represented in the red and blue histograms, respectively. The colored vertical dashed lines represent the median frontal beta and temporal alpha ERD onsets across participants. (e) The distribution of individual subjects’ temporal difference between frontal beta and temporal alpha ERD onsets is represented in the grey histogram. The black vertical dashed line represents no temporal difference; the grey vertical dashed line represents the median temporal difference between frontal beta and temporal alpha ERD onsets. A negative value indicates that the frontal beta onset precedes the temporal alpha onset, a positive value indicates that the frontal beta onset follows the temporal alpha onset.
