Functional Magnetic Resonance Imaging Of Brain Activation Related To Bimanual Coordination And Research Of Brain Dominance For Bimanual Finger Movements

Background and ObjectiveOur study used BOLD-based fMRI (functional magnetic resonance imaging based on blood oxygenation level) to identify the neural substrates of bimanual coordination. The brain dominance for bimanual finger movements was also researched.MethodsFifteen right-handed healthy volunteers (eight male and seven female) were scanned at a Gyroscan 1.5 Tesla magnetic resonance imaging scanner (Philips) while they were performing bimanual finger movements of different characteristics (mirror sequential finger movements or parallel sequential finger movements) at the rate of 1 Hz. The experiment consists of 4 runs. Every run consists of four task-blocks (12s) and four rest-blocks (18s). The task-block and restblock were presented by turns. The two different bimanual finger movements (mirror sequential finger movements or parallel sequential finger movements) were also presented by turns during task-blocks. Brain activity underlying bimanual coordination could be detected by contrasting the different brain activation of two kinds of bimanual finger movements. All subjects' average value of BOLD fMRI signal changes and its activation intensity were indicated with false colors, and covered to their relative structural images.ResultThe results showed both mirror sequential finger movements and parallel sequential finger movements activated a large area bilaterally covering the primary sensorimotor cortex (PSM), premotor area (PMA), parietal lobule (PAR), but more prominently in the right hemisphere than in the left hemisphere. Besides this activation, the right frontal lobe, the bilateral supramargiml gyms, the bilateral supplementary motor area (SMA), the bilateral cerebellum and bilateral basal ganglia (BG) are also activated. Activation of the right premotor area (PMA), bilateral parietal lobule (PAR), and fight inferior frontal gyrus were significantly stronger during the parallel sequential finger movements than during the mirror sequential finger movements. The fight hemisphere and left cerebellum seemed to be larger activated than the contra-lateral both during the parallel movements and during the mirror movements.ConclusionsThus, we can infer that the right PMA, bilateral PAR, and right inferior frontal gyrus appear to be related to the bimanual coordination of sequential finger movements. For righthanded healthy volunteers, Movements of the bimanual fingers are more dependent on right hemisphere and left cerebellum.