Functional overload and adaptive failure during dual-tasking in Ménière's disease

BackgroundMénière's disease (MD) impairs cognitive function, yet the dynamics of cognitive-motor interference are not well understood. This study investigated dual-task performance in MD, hypothesizing a greater performance cost for patients compared to healthy controls under combined cognitive and postural loads.MethodTwenty-nine patients with MD and 29 healthy controls participated in a dual-task paradigm that combined computerized dynamic posturography (CDP) with a cognitive battery assessing visuospatial, executive, and working memory functions. Performance was measured across Sensory Organization Test (SOT) conditions of increasing difficulty and analyzed using mixed-effects models.ResultsSignificant dual-task interference was found in the MD group only for reaction times on two cognitive tasks (Mental Rotation and Shifting Attention), where increasing postural difficulty disproportionately slowed performance relative to controls. No dual-task effects were found in the other four cognitive tasks (Visual Stroop Task, Backward Digit Span Task, Corsi Block Task, and Symbol Digit Coding Task). Importantly, concurrent cognitive tasks did not significantly impair postural stability in either group. Patients also exhibited baseline deficits specifically on visuospatial working memory tasks.ConclusionIndividuals with MD demonstrate selective cognitive-motor interference in demanding visuospatial and executive tasks, without concomitant deterioration in postural control under dual-task conditions. This suggests a posture first strategy and highlights a quantifiable, task-specific cognitive burden that is a clinically relevant feature of the disorder. Dual-task paradigms provide a sensitive method for assessing this impact, with clear implications for comprehensive patient evaluation and management.