title: Neuromimetic model of saccades for localizing deficits in an atypical eye-movement pathology.
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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Laboratory of Sensorimotor Research, National Institutes of Health, Bethesda, Maryland, USA. pierre.daye@gmail.com
authors.forename: Pierre M
authors.initials: PM
authors.lastname: Daye
authors.forename: Lance M
authors.initials: LM
authors.lastname: Optican
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Roze
authors.forename: Bertrand
authors.initials: B
authors.lastname: Gaymard
authors.forename: Pierre
authors.initials: P
authors.lastname: Pouget
mesh_terms: D000293:Adolescent; D001933:Brain Stem / Q000502:physiology; D002531:Cerebellum / Q000502:physiology; D003198:Computer Simulation; D005123:Eye / Q000503:physiopathology; D005133:Eye Movements; D005260:Female; D006801:Humans; D007859:Learning Disabilities / Q000150:complications; D008959:Models, Neurological; D009422:Nervous System Diseases / Q000503:physiopathology; D009474:Neurons / Q000378:metabolism; D009991:Oscillometry / Q000379:methods; D012044:Regression Analysis; D012438:Saccades / Q000502:physiology*; D014785:Vision, Ocular / Q000502:physiology