Interictal eye movement alterations in migraine with aura: impact of perceptual and cognitive load during reading

Migraine with aura (MwA) is a common neurological disorder often accompanied by visual and cognitive difficulties, including impaired attention and reading. Although previous studies have examined oculomotor function in migraine using specific and highly controlled paradigms, findings have been mixed, and eye movements during more natural tasks like reading remain understudied. The aim of this study was to explore interictal characteristics of eye movements in individuals with MwA during reading under increased cognitive and perceptual load. This study recruited 40 MwA patients and 30 age- and sex-matched healthy controls (HCs). MwA patients were tested during their interictal phase. Participants read short texts presented on an external monitor, consisting of six slides with varying background colors and contrast ratio, while their eye movements were recorded. The obtained data, including fixation and saccade parameters, were analyzed using a MANOVA, followed by non-parametric tests (Mann–Whitney U and Wilcoxon signed-rank tests). Results indicated a trend of impairments in eye-tracking parameters in MwA patients, which was most pronounced at the end of the reading session on the slide with the lowest contrast ratio, and manifested as lower fixation and saccade frequencies and longer average fixation durations. Further analysis of individual slides revealed consistent within-group differences in the MwA group, with patients showing poorer performance on most eye-tracking parameters on colored slides compared to white, a pattern not observed in HCs. This study reveals subtle eye movement imprairments in MwA patients during demanding reading tasks, particularly with colored backgrounds. These findings suggest that increased cognitive and perceptual load disproportionately impacts the visual system in MwA. Such delicate oculomotor dysfunctions could serve as observable markers for visual processing deficits in the interictal phase, and could guide a more personalized approach for a certain MwA subtype.