Psychosomatic Medicine 12:244-249 (1950)
© 1950 American Psychosomatic Society

The Effect of Low Oxygen on Psychologic Performance Tests in Psychoneurotic Patients and Normal Controls

¹ Department of Neurology and Psychiatry of the Harvard Medical School and the Department of Psychiatry of the Massachusetts General Hospital

A battery of psychomotor tests was administered to 31 normal control subjects and 30 psychoneurotic patients, first, while breathing 21 per cent oxygen (approximately sea level) and while breathing 10 per cent oxygen (approximately 17, 600 ft.). The total period of exposure to the low oxygen tension was about twenty minutes, the tests being given during the latter ten minutes of this period.

The average performance in both patient and control groups dropped in almost every instance despite the counteracting effects of practice. This general downward trend is consistent with previous studies of the effects of anoxia on performance.

The control subjects dropped more on the Reaction Time Tests while the patients showed a greater drop on the Tapping Speed and Stylus Tests.

However, when the two groups were compared directly with one another in regard to the amount of change at 10 per cent, it was found that there was no statistically significant difference between them.

The two groups were compared also in regard to the appearance of physical symptoms. It was found that they were very much alike in regard to type, frequency, and severity of symptoms reported. They differed only in that the controls seemed to experience headaches and giddiness more frequently, and the patients experienced more difficulty in breathing and more tremor and unsteadiness.