In space flight, the lack of sensory stimulation is one of the unavoidable problem to be solved. The study in author's laboratory, therefore, is carried out on analyzing the psychological and physiological alteration which may be produced by isolation from, or less exposure to, the sensory stimulation, particulary on the effect of long lasting application of weak and monotonous visual and auditory stimulation. It seems, however, that the suitable indicators for the experimental analyzing have not been established yet. In this paper, a summarized view of this problem is made refering our studies so far done, especially subjects' behavioral and electroencephalographic changes. Seven male university students were placed individually in a cylinder shaped isolation chamber for a period of three days. The behavior of the subjects was monitored at all times by a closed-circuit television system. Electroencephalographic records were taken by eight channel machine for two minutes every fifteen minutes during sensory deprivation experiment. It was found by every subjects that ego control level were gradually lowered in experiment progressing. In forty hours going by, logical thinking was broken off and hallucinations were occured by some subjects. And finally severe motivational losses were observed. EEG activity is also changed corresponding with behavioral impairments. It must be emphasized that EEG patterns in sleep showed marked differences between the first night and the last night during sensory deprivation.
|
