Vision impairment

Our eyes give us the most of the information about the world, therefore losing sight affects greatly one’s life. Visual information processing starts at the level of retina, a thin layer of tissue located at the back of the eyes. Light falls onto a specialized cell layer, the photoreceptors, and is converted into electrical impulses. These travel down the optic nerve to different regions in the brain where the visual percept is then interpreted. One cause of some of the most spread maladies which lead to vision impairment and, in extreme cases, the total loss of vision is the degradation of these cell layers within the retina. Over the last decades, different strategies have been employed in an attempt to compensate for the functions of the lost cell layers.

enTRAIN Vision

Within the enTRAIN Vision network, both academic and industrial research groups collaborate in order to study vision restoration strategies. The fifteen projects within this consortium are covering various topics, using computational methods aiming at studying the visual encoding in retina or lateral geniculate nucleus, experimental approaches using electrophysiology techniques, new materials that have the potential for a minimum invasive sight restoration or stimulation strategies, as well as various methods to assess the quality of the already existing therapies.

Towards object encoding using electrical and optogenetic artificial retinal stimulation at high spatio-temporal resolution

Colored circles mark the position of over one hundred recorded retinal cells.  They were stimulated by a square electrode, with the stimulus response decreasing with distance from the electrode.

Square electrode stimulates retinal cells

A relatively well studied approach to sight restoration is through electrical stimulation.

More recently, a new technique, the optogenetic therapy started to gain popularity. Light sensitive proteins are introduced into the eye through a viral injection. Following a certain period in which they bind to a target retinal cell, they can be photostimulated, emulating the role of the photoreceptor cells.

The focus of the project at TU Wien is investigating the retinal cells response to various types of stimulations.