Abstract
[Purpose] We examined the differences in brain activities of motor imagery between dexterity movement (DM, finger-to-thumb opposition movement tasks) and gross movement (GM, rotary motion tasks of the shoulder joint). [Subjects] Ten healthy young adults participated in this study (mean age 21.3±1.1). [Method] The participants performed DM and GM. These tasks were performed by motor imagery and voluntary movement (self-initiated movement and externally triggered movement). The changes of blood flow volume in the sensory-motor related areas were observed using near-infrared spectroscopy (NIRS). [Results] The motor imagery of DM did not significantly change in comparison with those of voluntary movements in any of the areas. The motor imagery of DM significantly increased in comparison with those of GM in the area of the premotor cortex and the sensory-motor cortex. [Conclusion] These results suggest the possibility that motor imagery of DM led to increases in neuronal activity that were greater than those of GM.
