Restauration de la vue grâce aux approches de neurophotonique

 

Mathieu Vanni

Université de Montréal

 

Domaine : neurosciences, santé mentale et toxicomanies

Programme Chercheurs-boursiers - Junior 1

Concours 2019-2020

The research will explore two aspects of rehabilitation in blinds 1) the development of a new generation of visual prostheses and 2) the development of new therapy to treat cortical blindness by using a new animal model.

In cases of blindness where the eyes cannot send any suitable neuronal signal to the brain, such as in glaucoma or Age-Related Macular Degeneration (AMD), one of the strategies considered is to bypass the eyes and directly stimulate the visual cortex with electrodes by transforming the information from a video camera. However, the results of this approach remain limited. My interpretation is that visual stimuli are very segmented at the level of the visual cortex and cannot simply be decomposed into spots of light as has been attempted. Moreover, electrical stimulation poorly simulates the biosignal and does not allow the information to be adequately delivered to the neurons of the cortex. To restore visual perception, I want to develop a new kind of neuroprosthesis considering the complexity of the cortical circuits while delivering a more "biological" signal, using the emerging field of optogenetics, which involves the stimulation of the brain with light. These devices will be developed on animals trained to perform visual tasks.

Blindness can also be observed while eyes are healthy in patients having brain injuries, such as a stroke within the visual cortex. My objective will be to develop a model of this type of pathology in mice which will allow the combined measurement of perception and cortical functions by imaging and optogenetic manipulation. In future, this platform will allow to test new therapeutic approaches based on non-invasive brain stimulation.