Res Vestib Sci.  2018 Dec;17(4):134-141. 10.21790/rvs.2018.17.4.134.

Identification of Vestibular Organ Originated Information on Spatial Memory in Mice

• Han GC
• Kim M
• Kim MJ

• KMID: 2436244
• DOI: http://doi.org/10.21790/rvs.2018.17.4.134

Abstract

OBJECTIVES
We aimed to study the role of vestibular input on spatial memory performance in mice that had undergone bilateral surgical labyrinthectomy, semicircular canal (SCC) occlusion and 4G hypergravity exposure.
METHODS
Twelve to 16 weeks old ICR mice (n=30) were used for the experiment. The experimental group divided into 3 groups. One group had undergone bilateral chemical labyrinthectomy, and the other group had performed SCC occlusion surgery, and the last group was exposed to 4G hypergravity for 2 weeks. The movement of mice was recorded using camera in Y maze which had 3 radial arms (35 cm long, 7 cm high, 10 cm wide). We counted the number of visiting arms and analyzed the information of arm selection using program we developed before and after procedure.
RESULTS
The bilateral labyrinthectomy group which semicircular canal and otolithic function was impaired showed low behavioral performance and spacial memory. The semicircular canal occlusion with COâ‚‚ laser group which only semicircular canal function was impaired showed no difference in performance activity and spatial memory. However the hypergravity exposure group in which only otolithic function impaired showed spatial memory function was affected but the behavioral performance was spared. The impairment of spatial memory recovered after a few days after exposure in hypergravity group.
CONCLUSIONS
This spatial memory function was affected by bilateral vestibular loss. Space-related information processing seems to be determined by otolithic organ information rather than semicircular canals. Due to otolithic function impairment, spatial learning was impaired after exposure to gravity changes in animals and this impaired performance was compensated after normal gravity exposure.

Keyword

Hypergravity; Spatial learning; Mouse; Vestibular lesion; Behavior

MeSH Terms

Animals
Arm
Automatic Data Processing
Gravitation
Hypergravity
Memory
Mice*
Mice, Inbred ICR
Otolithic Membrane
Semicircular Canals
Spatial Learning
Spatial Memory*