User:Paddyd2008

Patrick Degenaar is a lecturer in Neurobionics at the Institute of Biomedical Engineering and the Division of Neuroscience, Imperial College London. His teaches visual neuroscience, but is predominantly involved in optoelectronic retinal prosthesis and augmented vision systems for the visually impaired. He has developed a large UK based collaborative network pursue his aims, notably including the within Imperial College, the University of Oxford, the John Radcliffe hospital, and the Institute of Photonics, Stratchlyde. In addition both the EPSRC and BBSRC have provided large scale funding for his work.

Previously, he graduated with a first class BSc degree in applied physics (1996) and an M.Res in Surface Science (1997) from Liverpool University. Later he received a Monbusho scholarship to do a Bioelectronics and Bioimaging Ph.D. in the Japan Advanced Institute for Science and Technology, and graduated in 2001. After his PhD, he worked briefly as a software engineer in Amsterdam before moving to Imperial College to work as a post-doctoral research associate in 2002. At Imperial, he worked on interdisciplinary projects between the Physics and Chemistry, Electronic Engineering, and Bioengineering departments. Then in 2005 he received a RCUK fellowship and lectureship in June 2005.

Augmented Vision Research
Retinal dystrophies can lead to the total loss of vision in their final stages. However, in the early and intermediate stages there is some remaining functional vision. The visual cortex performs impressive image processing to use this residual trickle of visual information to build up the visual scene, but is hampered by having to (literally) guess the missing image components. Augmented vision research aims to image and enhance the visual and return this enhancement to the user in the form of a visual aid. Such visual enhancement techniques are presently being tested at the John Radcliffe Hospital in Oxford.

Optoelectronic vision Research
In patients with completely degenerate retina, the light sensing elements the rods and cones are destroyed, but often the retinal ganglion cells, which send information towards the visual cortex are intact. Thus the main hope of returning functional vision is through stem cell research or prosthetic implants. The latter has been the subject of research for decades but has many limitations at the present time. The main problem centres around the neural interface. Until recently the only realistic method of neural stimulation was through microelectrode arrays. However, both epi-retinal and sub-retinal electrical approaches have had many problems, and there has been very limited success in returning more than a few phosphenes to patients to date.

In 2003 a groundbreaking discovery by Nagel, Bamberg, Hegemann et al, showed that it was possible to insert a light activated ion channel into cell membranes. This channelrhodopsin-2 channel and associated proteins are now the basis for a revolution in the capability of neuroscientists to interact with nerve cells. The Neurobionics group is taking the development a step further by developing methods to photosensitize and optically communicate with the remaining retinal ganglion cells. This bypasses the need for destructive surgery, allows exact pinpoint control and offers a strong hope for returning some functional vision in the future.