by SPIE Noninvasive transcranial photobiomodulation (tPBM) experimental setup. (a) Placement of two pairs of optical probes on the forehead connected to atwo-channel near-infrared spectroscopy (2-bbNIRS) unit to capture brain activity. (b) Test regimen followed for each participant. (c) Light source, two spectrometers, and probe bundles for 2-bbNIRS measurement. (d) Arrows indicating the right and left sites...
