Method and apparatus for measuring cell metabolism through photobiomodulation

A system for in vivo and transcranial stimulation of brain tissue of a subject comprising at least one light source;

• a controller to control operation of the light source;
• a signal detecting unit and a processor configured to receive a signal from the signal detecting unit;
• analyze the signal and generate a feedback signal to the controller to control the light source until optimal results are obtained,
• wherein the detected signal is a broadband near-infrared spectroscopy (bbNIRS) image including one or more responding signals, on which two or more turning points and two or more threshold points are extracted, and a first line is generated by curve fitting to approximate the turning points on the responding signal while a second line is generated by curve fitting to approximate the threshold points on the responding signal, and the feedback signal is generated by comparing the responding signal, the first line, and the second line to determine the rate of brain tissue metabolism, and the feedback signal is generated.