Influence of a Plantar Hardness Discrimination Task on Brain Activity during the Task and Postural Sway While Standing on One Leg

Abstract

To investigate the effects of a plantar hardness discrimination task on brain activity and postural sway. [Participants and Methods] Twenty-six healthy adults participated in this study. The intervention group performed a plantar hardness discrimination task, and the control group performed an ankle plantar flexion task for 10 days. We measured postural sway with eyes open and eyes closed while standing on one leg, and used oxygenated hemoglobin concentration as an indicator of brain activity during a hardness discrimination task conducted before and after the 10-day intervention tasks. [Results] There were no significant differences in either brain activity or postural sway before and after the 10-day intervention tasks in both groups. In the intervention group, there was a positive correlation between the change in brain activity in the frontal association cortex and premotor cortex and the change in the postural sway with eyes open. [Conclusion] These results suggest that there is a relationship between postural sway and brain activity during the hardness discrimination task.