U.S. Navy saturation diving and diver neuropsychologic status

The neuropsychologic status of 25 male U.S. Navy saturation divers was assessed before and after saturation dives conducted at the Navy Experimental Diving Unit. Between 1982 and 1986, 5 dives to simulated depths of 198 to 335 msw were accomplished. Eighteen divers completed 1 dive, and 7 divers completed 2 saturation dives during this period. Dive durations ranged from 26 to 31 d, with helium-oxygen used as the breathing medium. On each dive the men engaged in strenuous, meaningful, in-water work on the bottom. Comparison of neuropsychologic assessment battery results pre- and postdives did not reveal permanent changes in neuropsychologic status. Transient alterations in affect, visual focusing, and physical activity level presented upon surfacing but resolved within 10 d.