Motor and Cognitive Effects of Cold Water Immersion under Hyperbaric Conditions

Abstract

Motor and cognitive tests were administered to four Navy divers under dry baseline conditions, in warm and cold shallow water, and again in cold water at 183 m. It was found that water resistance, cold water, and prolonged exposure to cold water at depth resulted in significant decrements in motor performance. None of these factors, however, consistently or reliably impaired cognitive performance. Those cognitive impairments which were found could probably be accounted for by impaired motor performance. The motor effects of prolonged exposure to cold water at 183 m may be related to either severe heat debt or CO₂ retention. These results indicate that present heating techniques are inadequate to protect divers from significant motor impairments after entering cold water at any depth, and from additional decrements after exposure to cold water for an hour at 183 m.