EXACT DOSE X-IRRADIATION OF VARIOUS REGIONS OF THE HEAD AND VISUAL SENSATIONS--X-RAY LOCATION METHOD OF STUDY OF THE REACTIVITY OF THE CENTRAL NERVOUS SYSTEM
- Ye.O. Burdianskaia
The primary substrate excited by threshold doses of x radiation of the normal human eye causes perception of a light flash in the retinal region. The threshold dose for the retina is about 1 mr; the threshold absorbed dose is about 1 mrad. Persons with a removed eyeball, on irradiation of the operated region with a frontal x-ray beam, perceive a flash of light at definite doses of radiation. Six persons taking part in an experiment saw a flash at doses of 17 to 150 mr (different observers saw flash at different doses) and did not see flash at doses of 5 to 90 mr. The cause of x-ray phosphene on frontal irradiation of the region of the removed eye with threshold doses is neither the reactivity of the optic nerve stump, the reactivity of the parts of the brain irradiated, nor the sensitivity of the skin receptors. In the cases considered, the cause of x-ray phosphene was irradiation of the retina of the nomnal eye by scattered x rays. The averaged coefficient of scatter was about 2%. On irradiation of the occiptal regions of the brain in subjects with normal eyes at a dose of about 150 mr, one subject perceived a flash of light. In this case, the absorbed dose for the occipital regions of the brain was about 40 mrad. The reason for this phenomenon must be explored. Stimulation of the cerebral formations (after atrophic changes in the visual tract and cortex) by x radia tion with a dose of up to 3 r, did not cause visual sensations. With the disposition of the beam, the absorbed dose for the chiasma was about 1 rad and for the occipital regions about 0.2 rad. In the study of threshold visual sensation and their causes on x irradiation of various regions of the head, it is important to apply defined doses of radiation. Scatter of the x rays in the head must be taken into consideration. (auth)
- Research Organization:
- Inst. of Biological Physics, Academy of Sciences, Moscow; Helmholz State Research Inst. for Diseases of the Eye, Moscow
- NSA Number:
- NSA-15-010708
- OSTI ID:
- 4087859
- Journal Information:
- Biophysics (U.S.S.R.) (English Translation), Vol. Vol: 5: No. 3; Other Information: Orig. Receipt Date: 31-DEC-61
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
Visual sensations induced by relativistic pions
Observations of visual sensations produced by Cerenkov radiation from high-energy electrons