Modulation of Functional Connectivity and Activation during Preparation for Hand Movement

Abstract

OCCUPATIONAL APPLICATIONS Our results illustrate the enhanced functional connectivity between motor-related brain regions and high-level cognitive brain regions during the transition period between rest and hand movements. These results suggest that the sensorimotor network is interacting with prefrontal areas during the transition period to maintain the preparation state. Both actual movement and the transition period without actual movement modulate brain activities. Capturing the detailed relationship of movement intention could be utilized to improve precision and latency of anticipation-based brain–computer interfaces. Furthermore, consistent with the neuroergonomic approach, this study demonstrates that functional near-infrared spectroscopy is a suitable tool for region-specific, task-related, and resting-state functional connectivity analysis. Our findings could enhance the development of more intuitive and natural interfaces between human and machine systems in diverse areas. The approach presented here could help create assistive devices that perceive and predict operators' intention of movements. TECHNICAL ABSTRACT Introduction: Traditional and new generations of neuroimaging techniques allow observing the modulation of brain activities during transition periods between rest and physical movement execution. A thorough understanding of the brain activity and functional connectivity changes during these transitions could contribute to increasing the precision and decreasing the latency of anticipation-based brain–computer interfaces, and improving human-system integration in general. Consistent with the neuroergonomic approach, functional near-infrared spectroscopy can monitor the outer cortex during extensive physical movement and in realistic settings using wearable and portable sensors. Methods: In this study, 19 healthy subjects were monitored with functional near-infrared spectroscopy during rest, a fist opening and closing task, and the transition period preceding the task. Functional connectivity analysis was used to evaluate how the transition period preceding the task modulated the brain activities. Results: There were several increases in functional connectivity during the transition period, especially between the right dorsolateral prefrontal cortex and the contralateral primary somatosensory and primary motor cortices, as well as the functional connectivity connecting the contralateral primary somatosensory cortex with the ipsilateral primary somatosensory cortex and the primary motor cortex. Regions located in the sensorimotor networks and right dorsolateral prefrontal cortex were also found to be activated during the transition period. Conclusions: These results demonstrate that the sensorimotor network is interacting with the high-level cognitive brain network during the transition period to maintain the preparation state. Furthermore, functional near-infrared spectroscopy is an emerging tool well-suited for region specific task-related and resting-state functional connectivity analysis. The results and the approach presented here suggest that operators' intention to move can be detected before the actual movement, and that could be employed for development of more intuitive and natural interfaces between human and machine systems.