Abstract
The smear during a saccade is known to guide subsequent saccades. Rapid flicker at frequencies above fusion can interfere with the smear, introducing visible artifacts (phantom array) and potentially interfering with reading. We conducted two experiments where the rapid naming of randomly ordered common words with high or low horizontal autocorrelation was measured. We would expect the spatial periodicity of the text and the phantom array to interact. The text was illuminated with LED lights that flickered at 60Hz, 120Hz, or 60kHz (Experiment 1) or at 60Hz, 600Hz, or with no flicker (Experiment 2). Reading speed was similar at 60Hz and 600Hz, and was faster at other frequencies or when the light was steady. Reading was slower with the high autocorrelation text at all frequencies. We categorized participants on the basis of the number of illusions they saw in patterns of stripes (pattern glare). The individuals who experienced pattern glare were slightly slower at reading and showed smaller differences between the flicker frequencies. The findings suggest that LED flicker can reduce efficiency in processing information, even at 600Hz where the phantom array is maximal. These effects may be exacerbated in individuals who experience pattern glare.