The impact of cognitive processes associated with image recognition on visuo-vestibular interaction

An increasing number of articles in the literature highlight the importance of saccadic remodulation in compensatory mechanisms, and the reappearance of SHIMP saccades following a vestibular insult correlates strongly with an improvement in symptoms reported by patients on the DHI. To assess the influence of attentional processes and working memory on visuo-vestibular interaction, we designed three independent yet interrelated experiments.In the first two experiments, perfectly healthy subjects (first experiment) and patients with a history of unilateral or bilateral vestibular deficits (second experiment) underwent vHIT in SHIMP mode and the Functional Head Impulse Test. The two tests were performed in the same session, initially separately ("separate protocol") and subsequently simultaneously ("combined protocol"). The mean latency of SHIMP saccades and their degree of clustering were analyzed, and finally, the recognition rate of the Landolt C. Subsequently, any variations in these parameters between the "disjoint protocol" and the "joint protocol" were assessed, and, in the second experiment, the differences between the "disjoint protocol" and the "joint protocol" were correlated with the severity of symptoms measured by the DHI. The aim was to verify whether, during the "joint protocol," the near-simultaneity of the two tasks, both mediated by shared parietal cortical substrates, altered any parameters. In the third experiment, we used vHIT in HIMP mode and fHIT, performed in disjointed and joint protocols. The objective was to verify whether the conjunction of saccadic function and cognitive load related to recognition could influence the latency and clustering of recovery saccades favorably.Conclusions: Results suggest visual recognition impacts visuo-vestibular interaction, supporting integrated dual-task protocols for ecological balance assessment and resolving clinical discrepancies, though larger multicenter studies are needed to confirm these preliminary findings.