- News & Events
Feb 22, 2017
11:00am-12:00pm, Feb 22, 2017
3402ABC, Djavad Mowafaghian Centre for Brain Health
Dr. Tim Murphy
Title: Is the thalamus driving or modulating the visual cortex?
The perception of external stimuli is traditionally considered to result solely from the processing of thalamic signals through direct cortico-cortical connections between areas organized in a hierarchical manner. In this corticocentric view, the potential role of higher-order (HO) thalamic nuclei that are reciprocally connected to cortical areas is not considered. Thus, new models of brain functions must take into account the fact that, besides direct communication between cortical areas through cortico-cortical connections, indirect communication through cortico-thalamo-cortical projections can also occur. However, the role of these transthalamic pathways remains obscure. Recent findings in my laboratory suggest that HO thalamic nuclei play a key role in sensory processing by enhancing the efficacy of local cortical processing and by coordinating the activity of distributed cortical units. My group is now testing this hypothesis at the visual system level by examining the impact of modulating the neural activity of the pulvinar, the HO visual thalamic nucleus, on the processing of information within and across areas of the visual cortex.
Christian Casanova obtained his PhD in Visual Neurosciences at the Université de Montréal in 1986. He then went to the School of Optometry of the University of California at Berkeley as a post-doctoral fellow on the neural basis of binocular vision. He did a second post-doc at McGill University on brain plasticity. In 1990, he was appointed Assistant Professor in the Department of Ophthalmology at the Faculty of Medecine of the Université de Sherbrooke. During that time, he became the director of the Brain and Perception axis of the FRQ-S Quebec Vision Network. He is still one of the board members of the Vision Network. He moved to the School of Optometry of the Université de Montréal in 1995. Christian Casanova became Assistant Director for Research and Graduate Studies of the Montreal School in 2005 and established the first PhD program in Visual Sciences in Quebec, in collaboration with the Department of Ophthalmology. He also headed the Vision Research Group in Visual Sciences of the Université de Montréal. During all these years, he sat on study sections of the main granting agencies in Quebec and Canada. He is heading the Montreal School of Optometry since 2011 while maintaining CIHR-funded research activities. His laboratory is currently studying the function of the main extrageniculate visual nucleus, the pulvinar as well as the role of endocannabinoids in visual processing using various approaches such as neuroanatomy, single cell recordings and imaging.