Loss of consciousness in healthy South African men: Incidence, causes and relationship to EEG abnormality.

The incidence of loss of consciousness (LOC) in 389 healthy young South African men was determined and surveyed in relation to ten precipitating stimuli. In 66% of the men the findings were related to electro-encephalographic abnormality. A relatively high group incidence of LOC was found, most frequently associated with head trauma. No relationship between LOC and electro-encephalographic abnormality emerged. The significance of the findings for aviation medical examiners is discussed.