Our research is characterised by the development and use of novel experimental and theoretical techniques and original ideas to study information processing in the sensory-neural circuits of flies. We have the expertise both to build innovative analytical methods and instruments and then exploit them scientifically, a unique and powerful combination.
Little is known about how the world is represented as brain activity patterns at cellular resolution, and how these patterns are updated, stored and recalled during learning and behaviour. Addressing these questions will lead to a real mechanistic understanding of how perception, memory and mind emerge from collective neural activity.
This Leverhulme Trust / Jane and Aatos Erkko Foundation funded project is aimed at studying the impact of intrinsic activity in neural communication at the first synaptic layer, which forms the lamina optic lobe in the fly eye. Specifically, we plan to test the hypotheses that responses to visual objects in lamina neurons change with: (H1) stimulus salience, (H2) competing stimulation, (H3) and the brain state; all of which are known to manifest changes in intrinsic activity. By combining the new experimental techniques that we have developed with a complete wiring diagram of the lamina and novel theoretical approaches to analyse and model neural activity (or animal behaviour), we wish to start deciphering the fundamental code how intrinsic activity modify visual information processing.
Research on primate vision has long recognised a division between 'what' and 'where' pathways that carry information about different object features. A similar distinction may apply to the first stages of the insect compound eye; based on different photoreceptor types (R1-R6 and R7/R8) feeding information into ‘where’ (motion) and ‘what’ (colour/form) pathways, respectively. However, the degree of independence in neural information and its processing between these pathways is unclear. Our preliminary evidence suggests that object feature representations in eye circuits result from network adaptation, which - instead of making the early neural pathways fully independent - preserves object identity in the population response by linking their dynamics in space-time.
Using state-of-the-art experimental and theoretical methods in fruit fly (Drosophila), we are now testing the hypothesis that excitatory/inhibitory contributions from individual cells, in which receptive fields differ in form/colour/motion selectivity, adapt object features over the neural pathways. This project is funded by Biotechnology and Biological Sciences Research Council (BBSRC).
Our work has been funded by research grants and/or fellowships from: BBSRC; EPSRC; The Royal Society; The Leverhulme Trust; Jane and Aatos Erkko Foundation; Gatsby Charitable Foundation; The Academy of Finland; The Wellcome Trust; University of Sheffield; ESRF (EU); DESY (Germany); National Science Foundation of China; National Key Laboratory of Cognitive Neuroscience and Learning, Beijing, China.