Multiple interactions between hemispheres of the brain modulating coupling of bilateral movements

Interaction between motor areas of the right and left hemispheres of the brain is important for generating bilateral coordinated movements. We investigated how bilateral coupling, which results from the interhemispheric interaction, is modulated during coordinated movements. We tried to estimate coupling and stability of bilateral movements during continuous movements of the right and left index fingers. The experimental results show that bilateral coupling strengthens during symmetric movements and same directional movements. However, coordination stabilities depend on only symmetry. The results suggest that two or more interhemispheric interactions contribute to control the bilateral coordinated movements.