The first step in saving a blacked-out diver is yelling “Breathe!” in his ears and calling his name. In the blacked-out state, vision and physical sensation disappear, but hearing remains, and it’s often heightened. Yelling, Pinon says, activates parts of the brain that have not yet shut down. This jolt can override the body’s reflex to close the throat so fresh air can enter the lungs.
