Bilateral vestibular deafferentation impairs performance in a spatial forced alternation task in rats

Area of Science:

• Neuroscience
• Vestibular System Research
• Behavioral Neuroscience

Background:

• The peripheral vestibular system significantly influences hippocampal function and associated behaviors.
• Long-term effects and potential recovery following vestibular lesions on the hippocampus remain under-investigated.

Purpose of the Study:

• To assess long-term spatial learning and memory deficits and recovery following bilateral vestibular deafferentation (BVD) in rats.
• To evaluate the impact of BVD on hippocampal function over extended periods.

Main Methods:

• Utilized the spatial forced alternation task in a T-maze to test learning and memory in rats.
• Compared performance of rats with BVD to sham-operated controls at 3 weeks, 3 months, and 5 months post-surgery.

Main Results:

• Rats with BVD exhibited significantly impaired performance compared to controls at all time points.
• Spatial learning and memory in BVD rats improved from chance levels at 3 weeks to significantly above chance by 5 months post-lesion.

Conclusions:

• Bilateral vestibular deafferentation leads to persistent, long-term impairments in hippocampal function and spatial learning.
• Evidence suggests a degree of functional recovery in spatial memory occurs beyond three months post-BVD.