What Is A G Loc ??? 😳 G-force induced loss of consciousness (abbreviated as G-LOC, pronounced "JEE-lock") is a term generally used in aerospace physiology to describe a loss of consciousness occurring from excessive and sustained g-forces draining blood away from the brain causing cerebral hypoxia. G-LOC is the direct result of loss of oxygen to the brain. Without oxygen, the brain is in severe and immediate danger. Any prolonged loss of oxygen is potentially lethal. Loss of oxygen for even sho