The complete set of connections in the brain is called our connectome. Over the last 20 years we have found out more about how this network is organised and how this organisation is linked to brain function [1,2]. I will outline how characteristic network features arise during evolution, how they are linked to brain function, and how they originate during individual brain development [3]. For example, small-world features enable the brain to rapidly integrate and bind information while the modular architecture, present at different hierarchical levels, allows separate processing of various kinds of information while preventing wide-scale spreading of activation [4]. Hubs play critical roles in information processing and are involved in many brain diseases [5]. Recent results show how spatial and temporal factors shape the development of these network features. Temporal factors, in terms of the birth time of neurons and their formation of connections, as well as spatial factors, in terms of the distance between neurons, influence the extent of bidirectional or long-distance connections, network modules, and network hubs. We also show how the spatial organisation of connectomes is linked to improved cognitive performance as seen through network dynamics and synchronization across regions [6]. Finally, I outline how network analysis and simulations can be applied to inform mental health interventions to improve cognitive performance. In particular, I will highlight noninvasive brain stimulation with focused ultrasound which is able to modulate activity in deep-brain structures.

[1] Martin, Kaiser, Andras, Young. Is the Brain a Scale-free Network? SfN Abstract, 2001.
[2] Sporns, Chialvo, Kaiser, Hilgetag. Trends in Cognitive Science, 2004.
[3] Kaiser. Changing Connectomes. MIT Press, 2020 mitpress.mit.edu/changing-connectomes
[4] Kaiser et al. New Journal of Physics, 2007.
[5] Kaiser et al. European Journal of Neuroscience, 2007.
[6] Hayward, Huo, Chen, Kaiser. Network Neuroscience, 2023.

Biography: Marcus Kaiser is leader of Neuroinformatics UK representing more than 600 researchers in the field (www.neuroinformatics.org.uk) and Chair of the Neuroinformatics Special Interest Group of the British Neuroscience Association. After studying biology and computer science, he obtained his PhD, funded by a fellowship from the German National Academic Foundation, from Jacobs University Bremen in 2005. In 2016, he was elected Fellow of the Royal Society of Biology. He is on the editorial boards of Network Neuroscience (MIT Press), PLOS Computational Biology, and Royal Society Open Science, and author of the first review on connectomics. Research interests are understanding the origin of brain disorders through modelling brain development and using models to inform therapeutic interventions, in particular using non-invasive brain stimulation (see www.dynamic-connectome.org ).