title: Noisy galvanic vestibular stimulation enhances spatial memory in cognitive impairment-induced by intracerebroventricular-streptozotocin administration.
abstract: There are several anatomical connections between vestibular system and brain areas construct spatial memory. Since subliminal noisy galvanic vestibular stimulation (GVS) has been demonstrated to enhance some types of memory, we speculated that application of noisy GVS may improve spatial memory in a rat model of intracerebroventricular streptozotocin (ICV-STZ)-induced cognitive impairment. Moreover, we attempted to determine the effect of repeated exposure to GVS on spatial memory performance. The spatial memory was assessed using Morris water maze test. The groups received 1 (ICV-STZ/GVS-I) or 5 (ICV-STZ/GVS-II) sessions, each lasting 30 min, of low amplitude noisy GVS, or no GVS at all (Control, ICV-saline, ICV-STZ/noGVS). Hippocampal morphological changes investigated with cresyl violet staining and the immediate early gene product c-Fos, as a neuronal activity marker, was measured. Hippocampal c-Fos positive cells increased in both GVS stimulated groups. We observed significantly improved spatial performance only in ICV-STZ/GVS-II group. Histological evaluation showed normal density in ICV-STZ/GVS-II group whereas degeneration observed in ICV-STZ/GVS-I group similar to ICV-STZ/noGVS. The results showed the improvement of memory impairment after repeated exposure to GVS. This effect may be due in part to frequent activation of the vestibular neurons and the hippocampal regions connected to them. Our current study suggests the potential role of GVS as a practical method to combat cognitive decline induced by sporadic Alzheimer disease.
authors.affiliation: Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mansoureh
authors.initials: M
authors.lastname: Adel Ghahraman
authors.affiliation: Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: zahmatkm@tums.ac.ir.
authors.forename: Maryam
authors.initials: M
authors.lastname: Zahmatkesh
authors.affiliation: Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Akram
authors.initials: A
authors.lastname: Pourbakht
authors.affiliation: Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Behjat
authors.initials: B
authors.lastname: Seifi
authors.affiliation: Department of Physiotherapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shohreh
authors.initials: S
authors.lastname: Jalaie
authors.affiliation: Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Soheila
authors.initials: S
authors.lastname: Adeli
authors.affiliation: Noor Pathobiology Laboratory, Tehran, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Niknami
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000633:toxicity; D003072:Cognition Disorders / Q000139:chemically induced / Q000150:complications* / Q000628:therapy; D004195:Disease Models, Animal; D004599:Electric Stimulation Therapy / Q000379:methods*; D007276:Injections, Intraventricular; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology; D008569:Memory Disorders / Q000209:etiology* / Q000628:therapy*; D009043:Motor Activity / Q000502:physiology; D009622:Noise; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin / Q000633:toxicity; D014722:Vestibule, Labyrinth / Q000502:physiology*
chemical_list: D000903:Antibiotics, Antineoplastic; D013311:Streptozocin
keywords: Cognitive impairment; Galvanic vestibular stimulation; Hippocampus; Spatial memory; c-Fos