Rightward Saccades Distort the Scaffold of Spatial Working Memory in ADHD

Attention-deficit/hyperactivity disorder (ADHD) is typically characterized by executive dysfunction, yet emerging evidence points to spatially asymmetrical features of cognition. We examined whether transsaccadic working memory (tWM), the mechanism that integrates visual and motor signals across eye movements, shows directional vulnerability in ADHD. Participants with ADHD completed a spatial tWM task in which memory arrays (one or three items) were presented before leftward, rightward, or fixation trials, and repositioned a probe to the remembered target location. For comparison, data from a previously tested neurotypical sample were included in group-level analyses. Errors were decomposed into systematic and unsystematic components. Compared to controls, ADHD participants showed a modest but reliable rightward-saccade disadvantage, with greater systematic distortions after rightward than leftward eye movements. Saccades disrupted working memory in both groups, but the typical load-dependent increase in unsystematic error observed in neurotypical participants was absent in ADHD. Two complementary interpretations may account for this asymmetry. The integration-imbalance hypothesis attributes it to weakened right-hemisphere contributions to spatial working memory, which impair integration of left-hemisphere oculomotor and right-hemisphere spatial signals during rightward saccades. Alternatively, the anchoring-disruption hypothesis suggests that rightward eye movements destabilize the spatial scaffold anchoring remembered locations, producing geometric distortions without increased error. Together, these findings identify a direction-specific fragility of visuomotor-cognitive coupling in ADHD not explained by general capacity limits. More broadly, they reveal a partial neglect-like pattern of transsaccadic vulnerability: selective impairment for rightward saccades without a left-field deficit—highlighting the utility of oculomotor paradigms for revealing hidden spatial asymmetries in neurocognitive function.