title: Neural correlates of the spontaneous phase transition during bimanual coordination.
abstract: Repetitive bimanual finger-tapping movements tend toward mirror symmetry: There is a spontaneous transition from less stable asymmetrical movement patterns to more stable symmetrical ones under frequency stress but not vice versa. During this phase transition, the interaction between the signals controlling each hand (cross talk) is expected to be prominent. To depict the regions of the brain in which cortical cross talk occurs during bimanual coordination, we conducted event-related functional magnetic resonance imaging using a bimanual repetitive-tapping task. Transition-related activity was found in the following areas: the bilateral ventral premotor cortex, inferior frontal gyrus, middle frontal gyrus, inferior parietal lobule, insula, and thalamus; the right rostral portion of the dorsal premotor cortex and midbrain; the left cerebellum; and the presupplementary motor area, rostral cingulate zone, and corpus callosum. These regions were discrete from those activated by bimanual movement execution. The phase-transition-related activation was right lateralized in the prefrontal, premotor, and parietal regions. These findings suggest that the cortical neural cross talk occurs in the distributed networks upstream of the primary motor cortex through asymmetric interhemispheric interaction.
authors.affiliation: Department of Cerebral Research, National Institute for Physiological Sciences, 38 Nishigonaka, Myodaijicho, Okazaki, Aichi 444-8585, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Aramaki
authors.forename: Manabu
authors.initials: M
authors.lastname: Honda
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Okada
authors.forename: Norihiro
authors.initials: N
authors.lastname: Sadato
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D001931:Brain Mapping; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005246:Feedback / Q000502:physiology; D005260:Female; D005385:Fingers / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D009048:Motor Skills / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D013647:Task Performance and Analysis