Figure 20

Figure represents the application of event-related fMRI to dystonia. Comparison of activated volume in motor cortical areas in a patient with dystonia and a normal subject is represented in the muscle relaxation and contraction task. In both tasks, the activated areas in the M1 and SMA were smaller for dystonia while in normal these activated areas were larger (see top 4 panels shown as A). A solid line indicates a mean signal change across ten trials shown as dots. The transient signal change timelocked to EMG offset was observable even in single trial (see panel B). Group data from eight patients and twelve healthy volunteers; demonstrate that activated volumes in the contralateral SM1 and SMA are greater in the healthy volunteers than in the dystonic patients. Figure is reproduced with permission of Oxford University Press from the reference [68].