Objective:To explore any effect of electrical stimulation of the right median nerve (RMNS) in modulating arousal patterns in the prefrontal cortex of a healthy adult.Methods:Twenty-three right-handed healthy participants received block-designed patterns of RMNS arousal. Functional near-infrared spectroscopy (fNIRS) was used to record any hemodynamic response in their prefrontal cortex. Changes in oxyhemoglobin (HbO), deoxyhemoglobin (HbR), and total hemoglobin (HbT) were analyzed by comparing the levels in stimulation blocks with resting-state periods.Results:fNIRS revealed significant activation of HbO signals in the left frontopolar area (channel 15) and the right frontopolar area (channels 37, 43 and 48) following RMNS arousal. There were significant differences in the HbR signals from the right frontopolar area (channel 41). There were, however, no significant differences in the HbT signals across all the measured channels.Conclusion:RMNS arousal enhances neurometabolic activity within the frontopolar sub-region of the prefrontal cortex in healthy adults.

Objective:To explore any effect of electrical stimulation of the right median nerve (RMNS) in modulating arousal patterns in the prefrontal cortex of a healthy adult.Methods:Twenty-three right-handed healthy participants received block-designed patterns of RMNS arousal. Functional near-infrared spectroscopy (fNIRS) was used to record any hemodynamic response in their prefrontal cortex. Changes in oxyhemoglobin (HbO), deoxyhemoglobin (HbR), and total hemoglobin (HbT) were analyzed by comparing the levels in stimulation blocks with resting-state periods.Results:fNIRS revealed significant activation of HbO signals in the left frontopolar area (channel 15) and the right frontopolar area (channels 37, 43 and 48) following RMNS arousal. There were significant differences in the HbR signals from the right frontopolar area (channel 41). There were, however, no significant differences in the HbT signals across all the measured channels.Conclusion:RMNS arousal enhances neurometabolic activity within the frontopolar sub-region of the prefrontal cortex in healthy adults.