Ambulatory monitoring of the electroencephalogram in high altitude mountaineers.
Twenty-nine 24 h ambulatory EEG recordings were obtained from 9 British Army mountaineers at heights ranging from 4115 to 6220 m during the period of acclimatization. Three individuals also had ambulatory sea-level EEGs. Sea-level clinical recordings were made on all the mountaineers. All the high altitude EEG recordings were readable and accurate sleep stage scoring was possible on 28 recordings. No paroxysmal activity, which had been reported previously, was noted in any of the high altitude EEGs. There was a marked reduction in stage 4 sleep compared to the amounts normally attained at sea-level, despite strenuous activity which might have been expected to increase slow wave sleep. There was a lesser reduction of REM sleep. These findings are consistent with complaints of poor quality sleep at high altitude, despite ample opportunity for sleep and the maintenance of health. The latter was attributed to careful acclimatization.
Finnegan
T P
TP
Abraham
P
P
Docherty
T B
TB
D000222:Adaptation, Physiological; D000328:Adult; D000532:Altitude Sickness / Q000503:physiopathology*; D000553:Ambulatory Care; D004569:Electroencephalography / Q000379:methods*; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D008297:Male; D008991:Monitoring, Physiologic; D009051:Mountaineering; D012895:Sleep, REM / Q000502:physiology