EFFECTS OF MILD HYPOXIA ON PERCEPTUAL-MOTOR PERFORMANCE - A SIGNAL-DETECTION APPROACH

Twelve healthy male subjects were required to make speeded judgements concerning the orientation of visual stimuli while breathing air at re duced partial pressure in a hypobaric chamber at altitudes of 7000 and 12 000 ft. A control condition was also conducted at sea level, and s ubjects received practice on the task at sea level prior to the commen cement of the experiment. Significantly slower response times were obt ained at 7000 and 12 000 ft relative to sea level. A signal-detection analysis showed that accuracy of judgement was significantly poorer at 12 000 ft, but oxygen deprivation has no systematic effect on respons e criterion.