Alex Fornito

Alex Fornito completed a PhD in the Departments of Psychology and Psychiatry at the University of Melbourne, Australia, followed by Post-Doctoral training at the University of Cambridge, UK. He is currently an Associate Professor, Australian Research Council Future Fellow, and co-Director of the Brain and Mental Health Laboratory in the Monash Institute of Cognitive and Clinical Neurosciences. Alex’s research uses cognitive neuroscience, network science and graph theory to understand brain network organization in health and disease. In particular, he focuses on the development and application of new methods to understand how brain networks dynamically adapt to changing task demands, how they are disrupted by disease, and how they are shaped by genetic influences. Together with co-authors Andrew Zalesky and Ed Bullmore, he recently published the first text book on network analysis for neuroscience, entitled Fundamentals of Brain Network Analysis.

Brain and Mental Health Laboratory, Monash Institute of Cognitive and Clinical Neuroscience, Monash University, Victoria, Australia

Talk title
The upside and downside of being highly connected in the brain

Talk abstract
Nervous systems are complex, interconnected networks. One ubiquitous property of such systems is that connections are not distributed evenly across neural elements. Instead, certain subsets of network nodes possess a relatively high number of connections, marking them as putative hubs. These hubs are strongly inter-connected with each other, forming a tight core, called a rich club, that plays a major role in integrating information across distributed neural systems. Hubs and rich-club organization have been identified in cellular networks measured at the level of individual neurons and synapses in the nematode worm C elegans, mesoscale inter-areal networks constructed through tract-tracing experiments in the mouse, and macroscale connectomes reconstructed with magnetic resonance imaging in humans. Thus, hub connectivity is a highly conserved and functionally important aspect of brain organization. Critically, hubs are also metabolically expensive. Hub connections extend over long distances, requiring greater cellular material and physical space, and hub areas consume more glucose to fuel their high levels of basal activity. This centrality and high cost of hubs renders them particularly vulnerable to disease, and there is growing evidence that pathology tends to accumulate within the highly connected elements of brain networks. In this talk, I will present studies that examine the critical role of hubs in brain function, their involvement in disease, and genetic influences on hub connectivity.