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Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm
Published on: April 28, 2020
Effect of gravity on vertical eye position.
1Service de Neurologie 1, Assistance Publique-Hôpitaux de Paris, Hôpital de la Salpêtrière, Paris, France. cp.deseilligny@psl.aphp.fr
Annals of the New York Academy of Sciences
|August 4, 2009
Summary
Gravity significantly impacts vertical eye position and movements. A new model proposes the crossing ventral tegmental tract (CVTT) as a key "antigravitational" pathway in the brainstem.
Area of Science:
- Neuroscience
- Ophthalmology
- Vestibular System
Background:
- Gravity's influence on vertical eye position and movements is increasingly recognized.
- Existing models do not fully explain gravity's role in eye movement control.
Purpose of the Study:
- To present a new model for brainstem upgaze pathways.
- To elucidate the role of the crossing ventral tegmental tract (CVTT) in counteracting gravity's effect on eye position.
Main Methods:
- Review of existing evidence and physiological observations.
- Analysis of nystagmus patterns in response to altered gravity and head positions.
- Correlation of clinical findings with proposed neural circuitry.
Main Results:
- A novel model identifies the CVTT as an "antigravitational" pathway.
- This pathway functions parallel to the medial longitudinal fasciculus.
- Evidence suggests the CVTT is modulated by head position to counteract gravity.
Conclusions:
- The CVTT plays a crucial role in maintaining vertical eye position against gravity.
- Gravity's direct effect on eyeballs explains various observed eye movement alterations.
- This model offers a comprehensive interpretation of gravity's influence on eye movements.
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