EyeSee - Eye movements and vision: coupling between saccadic adaptation and visuo-spatial perception
Final Report Abstract
Deciphering the properties and neural substrates of the effects of sensorimotor adaptation of saccadic eye movements on visual perception. Using the oculomotor system as a privileged model of sensorimotor transformations, we aimed at understanding the sensorimotor adaptation mechanisms which maintain the accuracy of saccadic eye movements over the medium-to-long term. Beyond maintaining efficient oculomotor exploration of our visual environment through motoric changes, this so-called saccadic adaptation has been proposed to yield changes of internal (neural) visual and oculomotor representations, keeping them consistent with motor commands. The present project aimed at testing this hypothesis by means of complementarity approaches in Humans (Lappe’s lab: computational modelling and psychophysics in healthy subjects; Pelisson’s lab: psychophysics in cerebellar patients, in healthy subjects coupled with functional neuroimaging-fMRI and in implanted epileptic patients coupled with intra-cerebral EEG-iEEG). This effort provided crucial fundamental knowledge, with high potential for clinical applications such as the rehabilitation of visual perception deficits through eye movements training. Computational, behavioral and physiological approaches of the coupling between saccadic adaptation and perceptual visual localization in Humans. Computational modelling has been a strong asset in our endeavor. The model developed in Lappe’s lab based on the behavior of healthy subjects provides a new theoretical framework of saccadic adaptation and of associated visual localization processes, addressing both the way saccade errors are encoded and trigger neural plasticity as well as which signals (visual target afferents, saccadic commands and/or oculomotor efference copy) are modified by plastic changes. The model’s behavioral predictions in the pathological context are currently compared to the performance of cerebellar patients assessed in Pélisson’s lab. Compared to healthy subjects’, these data suggest that the cerebellum contributes to adaptation-related changes of all three control signals delineated above. In parallel, the neuroimaging data of healthy participants and the unique iEEG recordings in implanted epileptic patients, both collected in Pélisson’s lab, have led to the first comprehensive identification of the brain networks associated with the error encoding and plasticity components of saccadic adaptation. Computational modelling and behavioral data have demonstrated that saccadic adaptation does not follow visual prediction error as usually thought, but instead results from a postdictive update of space after saccade landing. Consistent with this model’s architecture, saccadic and visuo-spatial behavioral performance in cerebellar patients disclosed the contribution of the cerebellum in both motor and perceptual components of saccadic adaptation. Finally, physiological recordings during saccadic adaptation provided an unprecedented description of brain networks involved in such oculomotor learning.
Publications
- A new approach to test the effect of saccadic adaptation on visual perception. GDR Vision meeting, Paris, 4-5 Oct. 2018
Cheviet A. and Pélisson D.
- A Boosting oculomotor plasticity through visuospatial attention. 20th European Conference on Eye Movements, Alicante (Spain), 18 - 22 August 2019
Pélisson, D., Nicolas, J., Métais, C., and Bidet-Caulet
- Impaired perceptual visual localization across saccades in a patient with parietal lesion. Poster at the GDR Vision meeting, Marseille, 10-11 Oct. 2019
Cheviet A., Pisella, L. and Pélisson D.
- Impaired visual localization across saccades in a patient with parietal lesion. 20th European Conference on Eye Movements, Alicante (Spain), 18 - 22 August 2019
Cheviet A., Pisella, L. and Pélisson D.
- Saccadic motor command adapts to post-saccadic target representation in pre-saccadic coordinates. 20th European Conference on Eye Movements, Alicante (Spain), 18-22 August 2019.
Masselink, J., and Lappe, M.
- Interaction between visual localization and adaptation of saccades : a study in cerebellar patients. Meeting of France Cerebellum Club, Cerebellum day, 30 -31 January 2020, Strasbourg
Cheviet A., and Pélisson D.
- A computational modelling study of saccadic adaptation and associated visual (mis)localization. eLife, 2021 Mar 9;10:e64278
Masselink, J., Lappe, M.
(See online at https://doi.org/10.7554/eLife.64278) - Brain substrates of reactive saccades adaptation and error processing. GDR Vision, Lille, 21-22 Oct. 2021
Métais, C., Nicolas, J., Cheviet, A., Diarra, M., Pélisson, D.
- Cerebellum drives motor adjustments and visual perceptual changes during size adaptation of reactive saccades. GDR Vision, Lille, 21-22 Oct. 2021
Cheviet A., Koun, E., Salemme, R., Froment-Tilikete, C. Pélisson D.
- The posterior parietal cortex processes visuo-spatial and extra-retinal information for saccadic remapping : a case study. Cortex, 2021, 139: 134-151
Cheviet, A., Pisella, L., and Pélisson, D.
(See online at https://doi.org/10.1016/j.cortex.2021.02.026)
