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Approved For Release ag2/ PB FPr 1\ IA-RDP96-00788R001300020001-6 ST-CS-01-169-72 July 1972 and its transformation in the subcortical structures; (d) recruit- ment only by the subcortex and motor cortex; (e) transformation in the visual cortex and recruitment by the deeper structures of the brain and motor cortex; (f) simultaneous transformation of the rhythm by all the structures recorded; (g) transformation by the visual cortex. All or a combination of these variations in brain activity could occur in the same experiment (30 to 60 min) (229). <A study was reported on non-rhythmic prolonged photo stimu- lation (230) and on the characteristics of sensory afterdischarge of the human brain to photic stimulation (231). A conclusion was drawn that the specificity of processes in the upper parts of the visual analyzer under a prolonged action of light depends on the inhibitory influences from the visual cértex. 5. (U) The Soviet literature contains reference to experimental work in the effect of high brightness on the rate of eye adapta- tion to darkness. Kartsev (232) reports that the rate of adaptation of central vision of both eyes to the darkness after light exposures of various durations (1.5,3,6 minutes) after illumination (20,000 to 80,000 lux) was studied in four test subjects in the age group 18-30. A white barium screen illumi- nated by direct sunlight was used as a light source. During adaptation to the darkness the central vision response time was proportional to the quantity of illumination during disadapta- tion. A value of approximately 8 x 10° lux per sec was used. Apparently the Soviets feel that they have determined the upper limits to the effects of brightness because Kartsev reports that central vision response remained unchanged with any further stimulus increase. Other researches have prepared curves for the computation of restoration to light sensitivity after exposure to superbright light flashes (233-235). Visual perception in aircraft pilots has also been studied (236). SECTION IIT - COLOR AND LIGHT 1. (U) The Soviets have reported that low intensity red light creates an irregular alpha rhythm in humans (237). Another study’ was conducted on the effects of low intensity red, green, and yellow light on humans (238). Physiological tests were adminis- tered to 412 females working in a film processing plant under red, green, or yellow light of low intensity 25 watt bulbs. Compléx shifts were found in the central and autonomic nervous system which included marked increases in optical rheobase and chronaxy and lengthening of the latent period of visual and motor reactions 82 CONTROLLED DISSEMINATION NO DISSEMINATION ABROAD CONFIDENTTAL (This page is UNCLASSIFIED)