Abstract: Disclosed herein are methods and devices of obtaining plethysmograph readings and utilizing plethysomography to identify when pilots are about to experience GLOC. Furthermore, in other embodiments, the invention pertains to methods and devices designed to warn a pilot that he/she is about to enter GLOC and/or automatically averting catastrophic damage or injuries by directing a plane being piloted to take predetermined corrective actions. Specifically disclosed is a system embodiment for assisting in the prevention of gravity induced loss of consciousness.

Abstract: The present invention relates to optimized gas supply utilizing photoplethysmography. Flow rate, pressure or amount of gas is adjusted as a function of blood oxygen saturation data, photoplethysmography signals, or both, obtained from the pulse oximeter probe.