Non-invasive brain cortex hemodynamic monitoring: A step towards motor disorder assessment via TD fNIRS.

The state-of-the-art in the diagnosis of motor disabilities includes the detection of anomalies while observing the patient performing specific movements. This method is affected by the subjectivity of perception conditioned by the operator's experience. A more rigorous approach involves the monitoring of cerebral response to motor stimuli by functional Magnetic Resonance Imaging. However, this solution forces the subject to maintain a static condition, therefore limiting the range of responses. Time-domain functional near-infrared spectroscopy (TD fNIRS) exploits the diffusion of picosecond laser pulses in cerebral tissue to allow for quantitative and non-invasive acquisition of brain functional activity. Given the latest hardware development pioneered by our research group, it is now possible to exploit compact and wearable TD fNIRS devices allowing for real-time brain monitoring of unconstrained moving subjects. To assess the potential of the TD fNIRS technique in the field of motor disorder, we studied motor cortex hemodynamic response functions on 16 healthy subjects performing standard physiotherapy protocols including goal-oriented and non-goal-oriented motor tasks.