High-current galvanic vestibular stimulation impairs working memory span, but not other executive functions

Patients with peripheral vestibular dysfunction (PVD) suffer not only from physical problems such as imbalance or vertigo but also from neuropsychological difficulties, including executive deficits. However, it is unclear whether the PVD directly causes executive problems. To examine the causal vestibular influence on executive functions, we induced either high-current (2 mA), low-current (0.8 mA), or sham current (0 mA) galvanic vestibular stimulation (GVS) in 79 healthy participants. Participants solved three tasks, measuring the core executive components (working memory, inhibition, cognitive flexibility) before and during GVS. High-current GVS impaired working memory span, but not inhibition and cognitive flexibility performance. Low-current GVS did not influence executive performance. Results indicate a causal vestibular influence on working memory span. Joint cortical areas of vestibular and working memory processing are discussed. Since high-current GVS in healthy participants serves as a model for an artificial vestibular dysfunction, our results could improve the diagnostics and therapy of patients with PVD.