Clinical Trial: Eye Movements and Visuo-spatial Perception

Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Interventional

Official Title: Coupling Between Adaptation of Saccadic Eye Movements and Visuo-spatial Perception and Attention Processes: a Behavioural Study in Humans.

Brief Summary: This research aims to highlight the key roles of the cerebellar and cortical fronto-parietal networks in the coupling of eye movements with visual perception and visuo-spatial attention.

Detailed Summary:

The first axe of this research focuses on the role of the cerebellum which has a major contribution to sensorimotor adaptation and more precisely in saccadic adaptation but the nature of this contribution is still debated. A classical assumption stipulates cerebellum has an exclusive action on saccadic burst generator in the brainstem whereas recent data increasingly support the view that cerebellum could also modulates cerebral cortex through a cerebello-thalamo-cortical pathway. On the other hand, several studies have shown that modification of saccade amplitude by saccadic adaptation leads to a distortion of the visual localization of briefly flashed spatial probes but no study to date has tested, the contribution of the cerebellum in these adaptation-induced mislocalizations. The main objective of this axe is to define the role of the cerebellum not only in saccadic adaptation, but also in mislocalizations which occur after adaptation. Moreover, in testing this assumption, arguments in favour -or in disfavor- of the action of the cerebellum on cortical stages dedicated to visuo-spatial perceptual processing will be provided. Besides, variability of cerebellar lesion (or cerebellar dysfunction) location in patients can lead to different pattern in saccadic adaptation and localization task performances. Identification of dissociations between these two abilities in some patients will define more precisely the role of the cerebellum in the coupling between saccadic adaptation and visuo spatial perception as an oculomotor plasticity territory and / or as a territory underlying the error signal coding generating this type of plasticity.

This second axe of this research aims to apply basic findings in healthy subject on the coupling between oculomotor plasticity and spatial attention to patients with parietal lesion, in order to evaluate a rehabilitation procedure for negle
Sponsor: Hospices Civils de Lyon

Current Primary Outcome: Saccadic adaptation efficiency [ Time Frame: At time of each experimental session, up to 2 months, since first experimental visit until last visit ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

• Evolution of localization-task performances [ Time Frame: At time of each experimental session, up to 2 months, since first experimental visit until last visit ]
  〖Improvement〗_performances= (〖Mislocalization 〗_post-〖Mislocalization 〗_pre)/〖Mislocalization 〗_pre
• Evolution of attentional performances assessed by neuropsychological tests of neglect [ Time Frame: At time of each experimental session, up to 2 months, since first experimental visit until last visit ]
  〖Improvement〗_performances= (〖Score 〗_post-〖Score〗_pre)/〖Score〗_pre

Original Secondary Outcome: Same as current

Information By: Hospices Civils de Lyon

Dates:
Date Received: March 29, 2017
Date Started: June 1, 2017
Date Completion: January 1, 2020
Last Updated: April 7, 2017
Last Verified: April 2017