Georgios Keliris "Neuromodulation of neural circuits involved in cognitive processes and brain disorders"

Monday 15 Apr 2024, 14:00 → 15:00 Europe/Brussels

B-30/0-000 - Big meeting room (CRC)

Abstract Dysfunction of neural circuits has a central role in cognitive functions such as learning and memory and underlies a wide range of brain disorders such as Alzheimer’s Disease, Autism, Epilepsy and many others. To identify changes that characterize neurological disorders we should in parallel explore the biology of neural circuits, understand their development and organization, and define the elements and processes essential to normal brain function. My work has used a multidisciplinary approach across scales (from cells to networks to behavior) to visualize neural circuits and brain networks in health and disease, perturb them to understand their function and malfunction, and assessed therapeutic approaches that utilize neuromodulation of large networks using chemogenetics. In addition, computational approaches and modeling have been used for analysis and to provide insights for future experiments and theories.

Bio Georgios A. Keliris finished his basic studies in Physics at the University of Cyprus (B.Sc., rank #1), and then moved to Tübingen, Germany with a scholarship from the German Academic Exchange Service (DAAD) to obtain a master’s degree (hons) in Neuroscience. This was a turning point in his career as he became intimately interested in major neuroscientific questions like the problem of perception and subjective experience. This has driven him to continue his studies for a Ph.D. in one of the world’s leading neuroscience laboratories (Max-Planck Institute for Biological Cybernetics; Dept. Physiology of Cognitive Processes; director: Prof. Nikos Logothetis) where he studied visual perception and plasticity in human and non-human primates using a battery of state-of-the-art techniques such as fMRI and multielectrode recordings. In 2007 he was the first to employ high-field (7Tesla) fMRI in awake non-human primates (NHP) that were trained using specifically designed paradigms and monitoring equipment to achieve imaging without movement artifacts. Moreover, he trained NHPs to report their subjective perception during bistable perception paradigms and demonstrated with electrophysiological recordings that only a minority of neurons (~20%) in primary visual cortex modulate their activity depending on the percept. After his PhD in the “Neural Correlates of Visual Perception”, he continued at the same institute first as post-doctoral fellow and later as a project leader and became very interested in the capacity of the nervous system for plasticity and reorganization after diseases afflicting the visual system. To this end, he has developed novel computational neuroimaging methods for estimating population based receptive field changes using fMRI in human and validated them with electrophysiology in macaques and used these techniques in a series of publications to monitor reorganization of visual areas in human subjects and a macaque suffering from early visual system damage. In 2015, he was appointed as an Assistant professor at the Bio-Imaging Lab, University of Antwerp, Belgium and developed a research line that investigates the effects of neuromodulation based on genetically encoded tools (optogenetics, chemogenetics), designed sensory input, and behavioral manipulations in rodent (disease) models (mice and rats). He is using a multimodal approach combining these and other techniques such as electrophysiology and calcium fiberoptic photometry measurements simultaneously with the fMRI in the scanner. Moreover, his team is developing and using whole brain dynamic functional connectivity measurements to identify global changes induced by neuromodulation. In 2022, he moved to the Institute for Computer Science at the Foundation for Research and Technology – Hellas, where in collaboration with computer scientists he develops novel analysis algorithms for large scale brain networks with the use of machine learning and artificial intelligence. In addition, he is a Visiting Professor at the Harvard Medical School (lab of Prof. Stelios Smirnakis) working in projects related to Alzheimer’s Disease, Implicit learning, MeCP2 duplication syndrome, and epilepsy using mesoscale recordings from a large number (thousands) of neurons using Calcium two-photon imaging.

 

From 2017 – 2022 he served as a board member of the Belgian Society for Neuroscience. He is an avid speaker and excellent teacher and supervisor (9 finished PhD students, 5 post-docs) and an author of > 60 peer reviewed publications in high-rank scientific journals such as Science, Nature Neuroscience, Neuron, PNAS, Trends in Cognitive Science and others.

 

 

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