Keith Mathieson, Royal Academy of Engineering Chair in Emerging Technologies

My research group develops optoelectronic devices to interface with neural systems in an effort to understand aspects of neural processing. We collaborate closely with leading neuroscientists and develop high-end technology using advanced semiconductor processing techniques.

Optogenetics: This technique allows neurons to be optically controlled (both activated and suppressed) and has become part of the toolkit allowing neuroscientists to further understanding of the brain. We develop novel photonic devices that allow spatio-temporal control over neural circuits by integrating micron-scale light sources (μLEDs) on to minimally invasive neural probes. These probes can optically excite neurons with laminar specificity and integrated microelectrodes can record the subsequent neural activity.

We work closely with neuroscientist, Dr Shuzo Sakata, who tests these probes in vivo. The work is summarised in the following publication: http://www.nature.com/articles/srep28381

The combination of high-density electrophysiological recordings with genetic manipulation techniques has the potential to make important discoveries in the field of neuroscience.

Retinal Prosthesis: We collaborate closely with the group of Prof. Daniel Palanker (Stanford) on the development of an optoelectronic retinal prosthesis to restore sight to patients with degenerative retinal diseases. Here we fabricate an implantable silicon chip that captures the visual scene through near infrared image projection, which also remotely powers the wireless device. A research driver for this project is the development of a device that can restore detailed vision to patients through a minmally invasive implant. For more information see the following publications: Nature Photonics  (doi:10.1038/nphoton.2012.104) and Nature Medicine (doi: doi:10.1038/nm.3851).

 Microelectrode Arrays: We have developed high-density microelectrode arrays for the recording of extracellular signals from retinal tissue. This state-of-the-art system is being used to study retinal processing and encoding of dynamic visual images at Stanford University (Chichilnisky Lab) and retinal development in the mouse at the University of California Santa Cruz (Sher Lab).

An example research output from this project is detailed in the  Nature publication (doi:10.1038/nature09424) where the system was used to study colour processing in the retina. It required close collaboration between technology groups at the University of Strathclyde, the University of California Santa Cruz (Litke & Sher), AGH University, Krakow (Dabrowski & Hottowy) and neuroscientists at Stanford (Chichilnisky).