Related Experiment Video
Updated: Jul 15, 2025
05:02
Using Unidirectional Rotations to Improve Vestibular System Asymmetry in Patients with Vestibular Dysfunction
Published on: August 30, 2019
7.3K
Compensatory saccade in the vestibular impaired monkey.
Yoshiko Kojima1,2, Leo Ling2, James O Phillips1,2
1Department of Otolaryngology-HNS, University of Washington, Seattle, WA, United States.
Frontiers in Neurology
|October 2, 2023
Summary
Vestibular deficits impair vision during head movements. This study shows that monkeys with injured vestibular systems generate covert saccades, a rapid eye movement that helps maintain clear vision, similar to human patients.
Area of Science:
- Neuroscience
- Ophthalmology
- Vestibular System
Background:
- Loss of the vestibulo-ocular reflex (VOR) impairs visual acuity during head movements.
- Patients with vestibular deficits use compensatory saccadic eye movements, including covert and overt saccades, to maintain vision.
- Covert saccades, occurring during head rotation, are crucial for central vestibular compensation.
Purpose of the Study:
- To investigate the neural mechanisms of covert saccades in an animal model.
- To demonstrate compensatory covert saccades in vestibular-impaired non-human primates.
Main Methods:
- Examined eye movements in non-human primates with injured vestibular end organs during the head-impulse test.
- Compared compensatory saccades with visually guided catch-up saccades.
Main Results:
- Compensatory saccades with latencies shorter than 250 ms were observed, indicating a non-visual origin.
- Short-latency saccades had lower peak velocities than longer-latency saccades.
- Longer-latency saccades resembled visually guided saccades.
Conclusions:
- The study demonstrates compensatory covert saccades in vestibular-impaired monkeys for the first time.
- Findings are consistent with observations in human patients with vestibular deficits.
- Understanding covert saccades can inform vestibular rehabilitation strategies.
Related Concept Videos
01:29The Vestibular System
39.7K
The vestibular system is a set of inner ear structures that provide a sense of balance and spatial orientation. This system is comprised of structures within the labyrinth of the inner ear, including the cochlea and two otolith organs—the utricle and saccule. The labyrinth also contains three semicircular canals—superior, posterior, and horizontal—that are oriented on different planes.
39.7K
01:15Equilibrium and Balance
4.8K
The inner ear assumes dual functionalities of auditory perception and equilibrium maintenance. The vestibule is the organ responsible for balance. This organ contains mechanoreceptors, specifically hair cells, endowed with stereocilia, which aid in deciphering information regarding the position and motion of our heads. Two intrinsic components, the utricle and saccule, help perceive head position, while the semicircular canals track head movement. Neurological messages initiated in the...
4.8K
01:28Major Somatic Sensory Pathways
1.0K
Sensory impulses related to touch, pressure, vibration, and proprioception from various body parts, such as the limbs, trunk, neck, and posterior head, travel to the cerebral cortex through the posterior column-medial lemniscus pathway. The pathway’s name derives from the two white-matter tracts that convey the impulses: the spinal cord's posterior column and the brainstem's medial lemniscus. First-order sensory neurons extend their axons into the spinal cord, forming the...
1.0K