MODELING HUMAN LASER EYE INJURY ON TARGET RECOGNITION PERFORMANCE USING SIMULATED SCOTOMAS

A laser accident patient's parafoveal visual field defect was modeled and his performance on a tank recognition task was compared with that of a participant in the modeled scotoma condition and in two central s cotoma conditions. The modeled parafoveal scotoma, and foveal and macu lar occluding scotomas were stabilized on the retina using a dual Purk inje Eye-Tracker and a multiplane digital image display. The simulated scotomas suppressed military target recognition functions in a manner consistent with previous studies. Neither central nor parafoveal scot omas were sufficient to reduce sensitivity to the patient's level. How ever, when the foveal and parafoveal scotoma functions were combined t o account for the patient's macular damage, prediction for patient per formance significantly improved. The data suggest that models of retin al damage from laser exposure must include not only visual field defic its but also deficits in high (visual acuity) and low spatial frequenc y visual function.