Prof Leon Lagnado – University of Sussex
Dr Sylvia Schroeder – University of Sussex
Dr Christian Wilms – Scientifica Ltd
Visual processing has been regarded as a sequential process from the extraction of simple to more complex visual attributes.
However, even early stages of this process are modulated by feedback projections from later impact (300 words max.) stages and input reflecting behavioural and internal brain states. Here we will determine how retinal, cortical and neuromodulatory inputs shape the responses of visual neurons in the superficial superior colliculus (SC). We will record neural responses to visual stimuli using two-photon imaging of neurons in the SC as well as axons originating in the retina, visual cortex, and brainstem nuclei. The awake animal will naturally experience various internal and behavioural states and will be monitored on video. The project incorporates the development of advanced imaging technology in collaboration with an industrial partner, Scientifica, that will enable us to record inputs and outputs of SC at sufficient detail, speed, and quantity by adapting a microscope to image two separate fields of view (FOVs) simultaneously. We will image at different depths to speed up volume imaging; and we will image single units and population activity in a small and large FOV simultaneously. The project advances our understanding of early visual processing and the integration of bottom-up and top-down neural signals. The prototype of a multi-region detection system will allow Scientifica to develop a full product, bringing the power of this method to researchers not able to adapt their microscopes themselves. In 2014, Scientifica won the Queen’s Awards for Enterprise, recognising the contribution Scientifica’s Multiphoton Imaging System has made to biomedical research around the world.