Relation of Signal Light Intensity to Physiologic End Points During +Gz Acceleration

摘要

Results of previous studies suggest that lowering the luminance of the signal lights lowers the blackout and grayout level during +Gz acceleration. In this study, variations in luminance of the central and peripheral signal lights in the range that is suitable for routine centrifuge operation failed to produce any detectable change in blackout or grayout levels. The visual phenomena described in the previous studies may have arisen mainly from such local changes in the eye as changes in visual threshold, retinal metabolism, and visual acuity; whereas, blackout obtained with light intensities used in this study resulted from hemodynamic changes caused by +Gz acceleration and possibly some local changes in the eye itself. (Author)