Prolonged dry apnoea: effects on brain activity and physiological functions in breath-hold divers and non-divers.

Purpose: The aim of the study was to investigate the effects of voluntary breath-holding on brain activity and physiological functions. We hypothesised that prolonged apnoea would trigger cerebral hypoxia, resulting in a decrease of brain performance; and the apnoea's effects would be more pronounced in breath-hold divers.

Methods: Trained breath-hold divers and non-divers performed maximal dry breath-holdings.