Undershoot-like signal associated with effort-induced mirror movements
Kuroki C, Oshio K, Ogawa S, Yokoi I
Hamano life science research foundation
Twenty six healty volunteers participated in this study. Subjects performed sequential high-speed unimanual finger/thumb tapping. BOLD and VASO fMRI were performed. Before and during scanning, EMG recording were made from bilateral flexor pollicis brevis muscle (data not shown). Mirror movements were seen in all subjects. In the ipsilateral brain region, the BOLD signal increase was much smaller than in cotralateral region, but a clear undershoot signal was seen. This might suggest a possibility of a separate mechanism behind the undershoot BOLD signal.