Bewegungswahrnehmung und Augenbewegungen bei Flickerbelichtung unbewegter visueller Muster

Abstract

Apparent movement perception without corresponding movement of the retinal image is elicited if the eyes move at an adequate velocity across intermittently illuminated stationary patterns which contain a certain amount of spatial periodicity (Lamontagne, 1973). This σ-movement also elicits an optokinetic nystagmus (σ-OKN) or (for closed figures) slow pursuit eye movements. The σ-OKN and the σ-movement are essentially caused by the internal feedback of the efferent motor signals controlling pursuit eye movements. In adult subjects we investigated the σ-effects applying different stimulus patterns (Figs. 2B—2E) and changed the following parameters of the 50 μs flashes illuminating the stationary stimulus patterns: Flash intensity, flash frequency, and the “jitter” of the flash intervals. To obtain the latter stimulus sequence, temporal noise was added to the sequence of regular flashes, thus producing flash sequences of a constant average flash rate, but a controllable variability in the interval distribution of successive flashes.