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Published in: Journal of Translational Medicine 1/2013

Open Access 01-12-2013 | Research

Neuromimetic model of saccades for localizing deficits in an atypical eye-movement pathology

Authors: Pierre M Daye, Lance M Optican, Emmanuel Roze, Bertrand Gaymard, Pierre Pouget

Published in: Journal of Translational Medicine | Issue 1/2013

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Abstract

Background

When patients with ocular motor deficits come to the clinic, in numerous situations it is hard to relate their behavior to one or several deficient neural structures. We sought to demonstrate that neuromimetic models of the ocular motor brainstem could be used to test assumptions of the neural deficits linked to a patient’s behavior.

Methods

Eye movements of a patient with unexplained neurological pathology were recorded. We analyzed the patient’s behavior in terms of a neuromimetic saccadic model of the ocular motor brainstem to formulate a pathophysiological hypothesis.

Results

Our patient exhibited unusual ocular motor disorders including increased saccadic peak velocities (up to ≈1000 deg/s), dynamic saccadic overshoot, left-right asymmetrical post-saccadic drift and saccadic oscillations. We show that our model accurately reproduced the observed disorders allowing us to hypothesize that those disorders originated from a deficit in the cerebellum.

Conclusion

Our study suggests that neuromimetic models could be a good complement to traditional clinical tools. Our behavioral analyses combined with the model simulations localized four different features of abnormal eye movements to cerebellar dysfunction. Importantly, this assumption is consistent with clinical symptoms.
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Metadata
Title
Neuromimetic model of saccades for localizing deficits in an atypical eye-movement pathology
Authors
Pierre M Daye
Lance M Optican
Emmanuel Roze
Bertrand Gaymard
Pierre Pouget
Publication date
01-12-2013
Publisher
BioMed Central
Published in
Journal of Translational Medicine / Issue 1/2013
Electronic ISSN: 1479-5876
DOI
https://doi.org/10.1186/1479-5876-11-125

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