Sensory processing, neuroethology, computational neurobiology.
Dr. Lewis’ work is focused on the neuronal dynamics involved in sensory processing - how the brain acquires and processes information to form memories and produce behaviour. In particular, his lab works on the “electric sense” of weakly electric fish through investigations at three different levels:
- Encoding of electrosensory information by neurons in the first way-station in the electrosensory pathway.
A brain slice preparation is used to explore the role of synaptic plasticity and neuronal feedback in the control of single neuron dynamics. Experimental and computational methods are combined in real-time using dynamic-clamp approaches, to assess the role of dynamic feedback in tuning the neural response to moving objects. (Collaborators: Andre Longtin)
- The roles of behaviour and electric field physics in shaping dynamic electrosensory stimuli.
A combination of behavioural studies and finite-element modeling is used to elucidate the salient features of naturalistic electrosensory stimuli. (Collaborators: Andre Longtin)
Investigations of the natural contexts under which putative electrocommunication signals are produced and detected, as well as on the biophysical mechanisms underlying the production of these signals.
John Lewis received his BSc in Physiology and Physics from McGill University in 1987. After a working stint with a biomechanics company, he returned to McGill to pursue graduate studies. He obtained his MSc in 1991 under the supervision of Leon Glass and Canio Polosa; this work involved the nonlinear dynamics of neural and genetic networks. In 1997, he obtained his PhD from the University of California, San Diego working with Bill Kristan. His doctoral work focused on the neuronal computations underlying sensory-motor reflexes in invertebrates. He then came to the University of Ottawa, Faculty of Medicine, as a postdoctoral fellow with Leonard Maler, beginning his work on sensory processing in the weakly electric fish. In 2003, he joined the Department of Biology at the University of Ottawa as an Assistant Professor.
Dr. Lewis is a past recipient of the Young Investigator Award from the International Society for Neuroethology, the Capranica Prize in Neuroethology, and a Senior Research Fellowship from the Canadian Institutes of Health Research.