Visuo-spatial memory enhancement by galvanic vestibular stimulation: A preliminary report

Navigation information is processed and stored in different brain areas such as hippocampus. Since multiple pathways has been reported between vestibular nuclei and hippocampus and also cognitive dysfunction specifically in spatial memory is induced by vestibular deficits، it can be assumed that vestibular system stimulation ameliorates spatial memory. The aim of study was to evaluate the effect of galvanic vestibular stimulation on normal individual’s spatial memory. In this experimental-interventional study، sixty 18-30-years-old women were randomly allocated in intervention and control groups. Intervention group undergone subthreshold bilateral bipolar galvanic vestibular stimulation and control group received sham stimulation. Stimulation was presented for 15 minutes. Corsi Block Tapping (CBT) test scores were compared before and after subthreshold bipolar galvanic vestibular stimulation exposure or no stimulation in each group and between groups. All test parameters were the same in both groups before stimulation (p<0. 050). There were significant improvement in block span، total score and learning score in intervention group after galvanic vestibular stimulation (p<0. 050)، no significant difference in delayed score (p=0. 600). Learning score was improved (p=0. 003) and delayed score was deteriorated (p=0. 010) in control group. Percentages of block span and total score in intervention group were significantly different compared to the other group (p<0. 050). Galvanic vestibular stimulation improves short-term and long-term spatial memory. This test may inherently have learning effect that is not influenced by stimulation.