Figure 1. Functional brain differences between controls and people who stutter during speech production with auditory feedback.

Results of functional MRI during speech production in PWS compared to Controls. Coloured maps of the Z-statistic for the F-test across the three feedback conditions are overlaid onto a single representative T1-weighted brain image from the subjects studied (thresholded at Z>3.5 for visualisation). Blue indicates areas where PWS had significantly less activity than Controls in at least one of the feedback conditions. Yellow/orange indicates areas where PWS had significantly more activity than controls in at least one of the feedback conditions. For axial and coronal slices the left side of the brain is shown on the left. Numbers next to each image indicate the coordinate in mm of that slice in x (for sagittal), y (for coronal) and z (for axial) relative to the orthogonal planes through the anterior commissure. vPMC - ventral premotor cortex; cOp - central operculum; SMC - sensorimotor cortex; CgS - cingulate sulcus; sn/stn/rn - substania nigra or subthalamic nucleus or red nucleus; pCbll - posterior lobe of cerebellum; Ins - insula; HG - Heschl’s gyrus.