Window to Understanding Brain Networks and Functions through Optogenetic Functional MRI (fMRI)

Abstract:

One grand challenge for the 21st century is to achieve an integrated understanding of brain circuits and networks, particularly the spatiotemporal patterns of neural activity that give rise to functions and behavior. Brains form highly complex circuits where circuit elements communicate using electrical and/or chemical signals. Such communications are typically facilitated through long-range projections that interconnect numerous regions, giving rise to a network-like property in the brain. Despite their importance, the functions of long-range projections remain poorly understood. Here, I will show you our recent developments in deploying multimodal techniques in-vivo on rodents to interrogate brain networks and their functions; leveraging on the strengths of optogenetics to enable cell-type specific neuromodulation, functional MRI (fMRI) to visualize brain-wide neural activity, and electrophysiology and behavioral measurements to explore the neural mechanism(s) and function(s) that underlie our observations. I will present key findings from our work in the thalamo-cortical, cortico-cortical, and cortical-subcortical circuits, including the unique dynamic spatiotemporal response properties of multisensory pathways as well as their functional relevance. From this talk, I aim to show you how utilization of multimodal brain imaging techniques can be vital in our quest to achieving an integrated and systemic understanding of large-scale brain-wide interactions.

 

Biography:

Alex T. L. Leong is currently a Research Assistant Professor in the Department of Electrical and Electronic Engineering, The University of Hong Kong. He received his doctorate in electrical and electronic engineering (MRI neuroimaging) from the same university, under the supervision of Prof. Ed X. Wu. For his Ph.D., he worked on combining optogenetics with fMRI in the study of spatiotemporal properties that govern neural activity propagations and interactions in the sensory thalamo-cortical network and the neural underpinnings of brain-wide functional connectivity as measured with resting-state fMRI. He received numerous awards in recognition of his work in functional neuroimaging, including International Society for Magnetic Resonance Medicine’s (ISMRM) Junior Fellow Award and OCSMRM’s Young Investigator Award, and has published in prestigious journals such as Nature Communications and PNAS. His current research interests include the use of neuroimaging, particularly MRI, to visualize complex and poorly understood brain networks in preclinical animal models; and develop novel non-invasive neuromodulation techniques that can be translated for therapeutic use.