The effect of repeated sessions of galvanic vestibular stimulation on target cancellation in visuo-spatial neglect: Preliminary evidence from two cases

Objective: In recent years it has emerged that the attentional disorder of visuo-spatial neglect can be overcome via artificial stimulation of the balance system. One means of achieving this is via galvanic vestibular stimulation (GVS), a simple procedure in which tiny, electrical currents are discharged to the part of the scalp overlying the vestibular nerves. Attempts to remediate neglect with GVS have utilized only a single session of stimulation and, although this can induce spontaneous recovery, symptoms resurface soon after stimulation. This study assessed whether repeated sessions induce longer carry-over.Methods: Two individuals diagnosed with neglect post-stroke received 5 days of sub-sensory, left anodal GVS. Performance was assessed via the letter and star cancellation tasks of the Behavioural Inattention Test on four occasions; 3 days before the start of stimulation, on the first and last day of stimulation and 3-days after stimulation.Results: Analyses of variance indicated that both particip...