Physiologic bases of G-induced loss of consciousness (G-LOC).

Exposure of pilots to high sustained +Gz (head to feet) or rapid onset of +Gz can produce a variety of pathophysiologic effects ranging from the loss of peripheral vision to total blackout and, finally, G-induced loss of consciousness (G-LOC). A G-LOC research program divided into four phases has been organized at USAFSAM/Crew Technology Division. In contrast to previous studies in acceleration, this program will focus exclusively on the ultimate problem in G-LOC; namely, inadequate cerebral perfusion leading to impaired brain energy metabolism, structure and function. The primary objective of this research program is to identify and arrange chronologically the numerous physiological and biochemical alterations in the brain that comprise the mechanism of G-LOC.