iCASE Studentship with Cambridge NeuroTech: Controlling brain activity and perception in primates

The activity of neurons in the primate brain has been linked directly to perception (Barlow, 1972; Parker & Newsome 1998). In Rhesus macaques, activity patterns of single neurons in visual cortex can reliably predict specific visual percepts (e.g. Britten et al 1996; Krug et al 2004). When combined with visual stimulation, focal electrical micro-stimulation of small groups of neurons can alter visual percepts in accordance with the visual preference of the stimulated neurons (Krug et al, 2013). Such interventions allow us to probe directly the neuronal codes that underlie higher cognitive brain functions. However, focal electrical micro-stimulation delivered on its own into visual cortex of monkeys or humans generally gives rise to simple phosphenes, rarely to more complex visual features (Cicmil & Krug, 2015).

The central aim of this project is to elucidate and control the spatio-temporal patterns that give rise to more complex visual percepts. In this project, the student will be able to utilise cutting edge, high-dimensional neuronal recording and stimulation probes, which are being developed by Cambridge Neurotech, our industrial partner. In order to progress beyond evoking simple, discrete phosphenes the electrical micro-stimulation system will use large-scale stimulation capabilities, delivered through potentially hundreds of electrode contacts, which themselves offer full-depth coverage of the cortical layers. This in turn will provide for complex spatio-temporal patterns of stimulation, which will be controlled by read-out patterns of neuronal recordings from the same part of visual cortex.

The specific project objectives are to record the pattern of neuronal activity across a three-dimensional section of visual cortex in response to judgements about complex visual stimuli. Based on the recorded spatio-temporal recording pattern for visual stimuli, cortical micro-stimulation protocols will be devised to ‘read back into cortex’ through interleaved stimulation probes. The student will evaluate neuronal recordings and behavioural responses obtained during cortical micro- stimulation and develop algorithms to determine the best patterns of spatio-temporal electrical micro-stimulation to visual cortex for the monkey to indicate a specific visual percept.

Training will be provided in behavioural training and testing of Rhesus monkeys, neuronal recordings and electrical micro-stimulation in awake behaving monkeys and quantitative analysis of neuronal and behavioural data. In addition, the placement with Cambridge NeuroTech will provide insight into the workings of a start-up company specialising in providing integrated, multidisciplinary solutions for cutting-edge electrophysiology.

This project investigates and controls neuronal signals that underlie cognitive brain function in primates. The findings of this research will underpin future research and developments in neuroprosthetic devices for stimulation and recording in humans.

This project is supported through the Oxford Interdisciplinary Bioscience Doctoral Training Partnership (DTP) BBSRC Industrial CASE (iCASE) studentship programme. The student recruited to this project will join a cohort of students enrolled in the DTP’s interdisciplinary training programme, and will be able to take full advantage of the training and networking opportunities available through the DTP. For further details please visit www.biodtp.ox.ac.uk.

Prospective applicants should contact the project supervisor Professor Kristine Krug ([Email Address Removed]) prior to submitting an application.

Applications for this project will be made via the Oxford Interdisciplinary Bioscience DTP. For further details please visit www.biodtp.ox.ac.uk.

Attributes of suitable applicants:

Applicants should have a strong background in science with a good undergraduate degree in a life or physical science subject (first class or upper second) and a specific interest in visual neuroscience. Strong quantitative skills, experience with electrophysiology, in animal behaviour or in programming, specifically with Matlab, are an advantage.