Vince Calhoun Founding Director & Distinguished University Professor, TReNDS Center
Vince D. Calhoun Dr. Calhoun is founding director of the tri-institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS) and a Georgia Research Alliance eminent scholar in brain health and image analysis where he holds appointments at Georgia State University, Georgia Institution of Technology and Emory University. He was previously the President of the Mind Research Network and Distinguished Professor of Electrical and Computer Engineering at the University of New Mexico. He is the author of more than 800 full journal articles and over 850 technical reports, abstracts and conference proceedings. His work includes the development of flexible methods to analyze functional magnetic resonance imaging data such as independent component analysis (ICA), deep learning for neuroimaging, data fusion of multimodal imaging and genetics data, neuroinformatics tools, and the identification of biomarkers for disease. His research is funded by the NIH and NSF among other funding agencies. Dr. Calhoun is a fellow of the Institute of Electrical and Electronic Engineers, The American Association for the Advancement of Science, The American Institute of Biomedical and Medical Engineers, The American College of Neuropsychopharmacology, and the International Society of Magnetic Resonance in Medicine. He served at the chair for the Organization for Human Brain Mapping from 2018-2019 is a past chair of the IEEE Machine Learning for Signal Processing Technical Committee. He currently serves on the IEEE BISP Technical Committee and is also a member of IEEE Data Science Initiative Steering Committee.
Executive control processes and flexible behaviors rely on the integrity of, and dynamic interactions between, large-scale brain networks. The right insular cortex is a critical component of a salience/midcingulo-insular network that is thought to mediate interactions between brain networks involved in externally oriented (central executive/lateral frontoparietal network) and internally oriented (default mode/medial frontoparietal network) processes. How these brain systems reconfigure with development is a critical question for cognitive neuroscience, with implications for neurodevelopmental pathologies affecting brain connectivity. I will describe studies examining how brain network dynamics support flexible behaviors in typical and atypical development, presenting evidence suggesting a unique role for the dorsal anterior insular from studies of meta-analytic connectivity modeling, dynamic functional connectivity, and structural connectivity. These findings from adults, typically developing children, and children with autism suggest that structural and functional maturation of insular pathways is a critical component of the process by which human brain networks mature to support complex, flexible cognitive processes throughout the lifespan.
Lucina Uddin Associate Professor, Department of Psychology, University of Miami
After receiving a Ph.D. in cognitive neuroscience from the psychology department at UCLA in 2006, Dr. Uddin completed a postdoctoral fellowship at the Child Study Center at NYU. For several years she worked as a faculty member in Psychiatry & Behavioral Science at the Stanford School of Medicine. She joined the psychology department at the University of Miami in 2014. Within a cognitive neuroscience framework, Dr. Uddin’s research combines analyses of resting-state fMRI and diffusion weighted imaging data to examine the organization of large-scale brain networks supporting executive functions. Her current projects focus on understanding dynamic network interactions underlying cognitive inflexibility in neurodevelopmental disorders such as autism. Dr. Uddin’s work (over 125 publications) has been published in the Journal of Neuroscience, Cerebral Cortex, JAMA Psychiatry, Biological Psychiatry, PNAS, and Nature Reviews Neuroscience. She was awarded the Young Investigator award by the Organization for Human Brain Mapping in 2017.
The Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) consortium is a worldwide, largely volunteer research collaboration that recently celebrated its 10th year. In that time, it has become a model of large-scale, imaging data re-use for meta- and mega-analysis, leading to numerous results in genetic effects on brain structure, clinical effects on brain structure and function, and methods for analysis of heterogenous structural and functional data. Clinical research domains range from schizophrenia to bipolar disorder to Parkinson's disease, sleep disorders, HIV and addiction, while methodological developments span gray matter volumes, subcortical shape, sulcal and gyral depth, white matter tract based statistics, and resting state analyses, with recommendations for applying an ENIGMA approach to task-based fMRI are in development. These efforts highlight both the value of combining data analyses, along with the challenges of combining data from studies collected for different reasons in different environments. I will review some of the current efforts underway across the more than 50 working groups within ENIGMA, along with the implications for these kinds of large-scale analyses in the future.
Jessica Turner Associate Professor, Neuroscience, Psychology, TReNDS Center & Georgia State University
Dr. Turner received her PhD in Psychology (Cognitive Sciences) from the University of California, Irvine, followed by a post-doctoral position at Rutgers the State University of New Jersey, learning single-cell recording and optical imaging techniques. Having determined that invasive measures were not her preferred techniques, she moved into functional and structural neuroimaging and was fascinated by the ability to measure brain function non-invasively. Since then, her research program uses neuroimaging of clinical populations to improve understanding of the structural and functional circuitry underlying mental illness and health, and integrates several approaches: The combination of imaging with genetics, to identify genotypes which might help individualize treatment and prognosis; structural and functional imaging across multiple institutions to develop robust clinical neuroimaging studies; use of these neuroimaging methods in schizophrenia and other disorders to determine the relationship between brain volume and functional characteristics with disease status and symptom profiles; and large-scale neuroimaging data sharing to support the international collaborations needed to perform imaging genetics analyses. Since 2013 she has been at Georgia State University as faculty in psychology and neuroscience, and the head of the Imaging Genetics and Informatics Laboratory.Website: https://psychology.gsu.edu/profile/jessica-turner/
The long predominant paradigm in neuroimaging has been to compare (mean) local volume or activity between groups, or to correlate these to behavioral phenotypes. Such approach, however, is intrinsically limited in terms of possible insight into inter-individual differences and application in clinical practice. Recently, the increasing availability of large cohort data and tools for multivariate statistical learning, allowing the prediction of individual cognitive or clinical phenotypes in new subjects, have started a revolution in imaging neuroscience.
The transformation of systems neuroscience into a big data discipline poses a lot of new challenges, yet the most critical aspects is the still sub-optimal relationship between the extremely wide feature-space from neuroimaging and the comparably low number of subjects. This, however, is only true when approaching neuroimaging machine-learning in a naïve fashion, i.e., when ignoring the large body of existing work on human brain mapping. The regional segregation of the brain into distinct modules as well as the large-scale, distributed networks provide the fundamental organizational principles of the human brain and hence the basis for cognitive information processing. Importantly, both can now be mapped in a highly robust fashion by integrating information on hundreds or even thousands of individual subjects to provide a priori information.
This talk will outline the fundamental principles of topographic organization in the human brain and the robust mapping of functional networks. I will then illustrate, how this knowledge on human brain organization can be leveraged for inference on socio-affective or cognitive traits in previously unseen individual subjects or psychopathology in mental disorders. Providing a bidirectional translation, such application will in turn provide information on the respective brain regions and networks.
Layer fMRI, requiring high field, advanced pulse sequences, and sophisticated processing methods, has emerged in the last decade. The rate of layer fMRI papers published has grown sharply as the delineation of mesoscopic scale functional organization has shown success in providing insight into human brain processing. Layer fMRI promises to move beyond being able to simply identify where and when activation is taking place as inferences made from the activation depth in the cortex will provide detailed directional feedforward and feedback related activity. This new knowledge promises to bridge invasive measures and those typically carried out on humans. In this talk, I will describe the challenges in achieving laminar functional specificity as well as possible approaches to data analysis for both activation studies and resting state connectivity. I will highlight our work demonstrating task-related laminar modulation of primary sensory and motor systems as well as layer-specific activation in dorsal lateral prefrontal cortex with a working memory task. Lastly, I will present recent work demonstrating cortical hierarchy in visual cortex using resting state connectivity laminar profiles.
Peter Bandettini Chief, Section on Functional Imaging Methods, National Institute of Mental Health
Dr. Bandettini received his undergraduate degree in Physics from Marquette University in 1989, and his Ph.D. in Biophysics in 1994 at the Medical College of Wisconsin where he led the effort to carry out one of the first successful experiments in functional MRI. He completed his post doc at the Massachusetts General Hospital NMR Center in 1996. After spending three years as an Assistant Professor at the Medical College of Wisconsin he was recruited in 1999 to become Director of the Functional MRI Facility at and Chief of the Section on Functional Imaging Methods the National Institutes of Health. Recently, he has become the founding Director of the Center for Multimodal Neuroimaging at the National Institute of Mental Health and has started a Machine Learning group and a Data Sharing group. He also recently completed a 6 year tenure as Editor In Chief of the Journal, NeuroImage. He is the recipient of the 2001 OHBM Wiley Young Investigator Award, and in 2020 was awarded the ISMRM Gold Medal. His research focus over the past 29 years has been on advancing functional MRI in all ways, including novel fMRI methods in acquisition, processing, and paradigm design. He current research focus is high resolution layer fMRI, dynamic connectivity, understanding and mitigating physiologic noise in fMRI time series, and deriving individual specific information using fMRI. He has published over 175 papers and has presented over 390 invited lectures.
We discuss recent attempts to understand complex brain dynamics at large scale using approaches from statistical physics. The motivation to adopt this approach is rooted in a more general question: "Why life is complex and –most importantly– what is the origin of the over abundance of complexity in nature?" This fundamental problem “is screaming to be answered but seldom is even being asked”, paraphrasing the late Per Bak.
In this lecture we will justify the approach by reviewing our attempts across several scales to understand the origins of complex biological problems from the perspective of critical phenomena. We will then offer an overview of the experimental and numerical results pertaining to complex aspects of large scale brain dynamics.
Dante Chialvo Head, Center for Complex Systems & Brain Sciences (CEMSC3), Universidad Nacional de San Martin
Dr. Dante R. Chialvo received his diploma in 1982 from the National University of Rosario, in Argentina. In 1985 was appointed Professor of the Department of Physiology of the University of Rosario. From 1987 to 1992 was Associate Professor in the State University of New York (Syracuse, NY) in the Department of Pharmacology and latter in the Computational Neuroscience Program. Between 1992 and 1995 was associated with the Santa Fe Institute for the Sciences of Complexity, in Santa Fe, New México. Until 2010, he was Full Professor at Northwestern University (Chicago), and UCLA, when he returned to Argentina as Principal Investigator of Conicet (Argentina).
Currently he is Full Professor and head of the Center for Complex Systems and Brain Sciences (Cemsc3) at the UNSAM (Universidad Nacional de San Martin) in Buenos Aires, Argentina.
Throughout these years, he has been Visiting Professor at numerous universities including Wuerzburg University (Germany), University of Copenhagen (Denmark), The Rockefeller University (U.S.A.), University of the Balearic Islands, University of Barcelona, University Complutense of Madrid, (Spain), Naples (Italy) and University of Rosario, University of Cordoba (Argentina), Universidad Mayor de San Andres, La Paz, (Bolivia) , Jagellonian Univ. (Krakow) among others.
Dr. Chialvo has published more than 100 scientific papers, all dedicated to understand natural phenomena from the point of view of Nonlinear Dynamics of Complex Systems. His work covers a wide range of topics, including the mathematical modeling of cardiac arrhythmias, the study of molecular motors as stochastic ratchets, neural coding, and self-organization and collective phenomena in ants swarms, brain and communities, among others. In 2005 he was the recipient of a Fulbright US Scholar Award (2005), in 2006 the Distinguished Visiting Professor of the University Complutense, (Psychology Department), Madrid, Spain, Visiting Professor Award of the Seconda Università degli Studi di Napoli, Aversa Italy and elected Fellow of the American Physical Society in 2007.
The brain has all of the hallmarks of a complex system, with meaningful activity occurring at a wide range of spatial and temporal scales. When measured with resting state fMRI, all of this activity is compressed into a single measurement of the resulting hemodynamic response for each voxel at each time point. However, by leveraging the spatial, temporal and spectral properties of different types of activity, we may be able to identify signatures in the rs-fMRI signal. In this talk, I will describe some of the types of activity that we expect to contribute to the rs-fMRI signal and features that might allow us to selectively extract them for use in research or the clinic.Recommended Articles:
Shella Keilholz , Georgia Institution of Technology
Dr. Shella D. Keilholz received her B.S. degree in physics from the University of Missouri Rolla (now Missouri University of Science and Technology) and her Ph.D. degree in engineering physics at the University in Virginia. Her thesis focused on quantitative measurements of perfusion with arterial spin labeling MRI. After graduation, she went to Dr. Alan Koretsky’s lab at the NIH as a Postdoctoral Researcher to learn functional neuroimaging. She is currently a Professor in the joint Emory/Georgia Tech Biomedical Engineering Department, Atlanta, GA, USA and Program Director for the 9.4 T MRI. Her research seeks to elucidate the neurophysiological processes that underlie the BOLD signal and develop analytical techniques that leverage spatial and temporal information to separate contributions from different sources.
Juan (Helen) Zhou Principal Investigator, Center for Sleep and Cognition, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore
Jeffrey Malins Assistant Professor, Department of Psychology, Georgia State University
Nice to meet you! I am an assistant professor in the Department of Psychology at Georgia State University, and I am also affiliated faculty with the GSU Center for Research on the Challenges of Acquiring Language and Literacy and the GSU Neuroscience Institute. Prior to joining the faculty at GSU, I was an Associate Research Scientist in Pediatrics at Yale University. I also completed a postdoctoral fellowship at Haskins Laboratories, where I remain a Research Affiliate.
My research focuses on the brain networks that support reading, spoken language processing, and attentional control. I use neuroimaging to study how these networks overlap, diverge, and change over the course of learning. I also examine how different biological, cognitive, and environmental factors shape the connectivity of these networks. In my research, I work with numerous populations of learners, including school-age children, adolescents, and adults; individuals with reading, language, and/or attention deficits; and individuals who speak or read more than one language.
Over the past few years, I have had the pleasure of working with several collaborators in the GSU community to study reading development in children. Using fMRI, we are currently looking at the intersection between the brain networks underlying reading and attentional control (Arrington, Malins, et al., 2019, Developmental Cognitive Neuroscience). We are also following up on a recent study suggesting that a certain amount of variability in brain activity may be beneficial for reading growth (Malins et al., 2018, Journal of Neuroscience). In the future, I am particularly interested in examining how diverse experiences with language – such as bilingual language experience in children – help to shape the brain networks that support literacy skills.
I look forward to continuing to build connections with the neuroimaging community in Atlanta and beyond. Together, I hope we can find ways to connect brain research with current practices in education in order to help individuals reach their learning potential.
I will recall how reduction in variance and reduction in surprise are two similar (and sometimes identical) ways of investigating dependencies in dynamical systems.
I will present how this framework can be used to investigate higher order dependencies to find information-based multiplets and to allow for a more precise characterization of multivariate patterns of connectivity.
I will then show how we can look at interactions across temporal scales, and present some applications in neuroscience.Recommended Articles:
Daniele Marinazzo Professor of Neuroimaging Data Analysis, Ghent University
I am a statistical physicist (MSc 2001, PhD 2007, University of Bari) who has always worked towards the characterization of the dynamics of complex systems, mainly the brain. From 2008 to 2011 I was a postdoc at CNRS, University Paris 5, performing in vivo electrophysiology and dynamic clamp experiments. Since 2011 I am Research Professor of Data Analysis at Ghent University, Belgium. I teach techniques of neuroimaging data analysis; I am member of the Belgian node of the International Neuroinformatics Coordinating Facility (INCF) and a mentor for Google Summer of Code on their behalf. I am co-editor in chief of Neurons, Behavior, Data Analysis, and Theory, deputy editor of PLOS Computational Biology, editor of NeuroImage, Network Neuroscience, Brain Topography, and PLOS One, editor of the PLOS complexity channel, and referee for many journals in the field of neuroscience and applied physics.
This talk will focus on the modelling of resting state time series or endogenous neuronal activity. I will survey recent developments in modelling distributed neuronal fluctuations – spectral dynamic causal modelling (DCM) for functional MRI [1, 2] – and how this modelling rests upon functional connectivity. The dynamics of brain connectivity has recently attracted a lot of attention among brain mappers. I will also show a novel method to identify dynamic effective connectivity using spectral DCM . Further, I will summarise the development of the next generation of DCMs towards large-scale, whole-brain schemes which are computationally inexpensive , to the other extreme of the development using more sophisticated and biophysically detailed modelling based on the canonical micro circuits Recommended Articles:
Adeel Razi Associate Professor & ARC DECRA Fellow, Turner Institute for Brain and Mental Health, Monash University
Adeel Razi is an Associate Professor at the Turner Institute for Brain and Mental Health, Monash University, Australia, where he is the Head of the Computational Neuroscience Laboratory. His research is cross-disciplinary, combining engineering, physics, and machine-learning approaches, to model complex, multi-scale, network dynamics of brain structure and function using neuroimaging. He is currently Australian Research Council DECRA Fellow (2017-2020) and has also been awarded NHMRC Investigator (Emerging Leader) Fellowship (2021-2025). He is an `Honorary’ Senior Research Fellow at the Wellcome Centre for Human Neuroimaging of University College London, where he also worked from 2012 to 2018. He received the B.E. degree in Electrical Engineering from the N.E.D. University of Engineering & Technology, Pakistan, the M.Sc. degree in Communications Engineering from the University of Technology Aachen (RWTH), Germany, and the Ph.D. degree in Electrical Engineering from the University of New South Wales, Australia in 2012.
State-of-the-art magnetic resonance imaging (MRI) provides unprecedented opportunities to study brain structure (anatomy) and function (physiology). Based on such data, graph representations can be built where nodes are associated to brain regions and edge weights to strengths of structural or functional connections. In particular, structural graphs capture major neural pathways in white matter, while functional graphs map out statistical interdependencies between pairs of regional activity traces. Network analysis of these graphs has revealed emergent system-level properties of brain structure or function, such as efficiency of communication and modular organization.
In this talk, graph signal processing (GSP) will be presented as a novel framework to integrate brain structure, contained in the structural graph, with brain function, characterized by activity traces that can be considered as time-dependent graph signals. Such a perspective allows to define novel meaningful graph-filtering operations of brain activity that take into account smoothness of signals on the anatomical backbone. This allows to define a new measure of “coupling” between structure and function based on how activity is expressed on structural graph harmonics. To provide statistical inference, we also extend the well-known Fourier phase randomization method to generate surrogate data to the graph setting. This new measure reveals a behaviorally relevant spatial gradient, where sensory regions tend to be more coupled with structure, and high-level cognitive ones less so. In addition, we also make a case to introduce the graph modularity matrix at the core of GSP, in order to incorporate knowledge about graph community structure when processing signals on the graph, but without the need for community detection. Finally, recent work will highlight how the spatial resolution of this type of analyses can be increased to the voxel level, representing a few hundredth thousands of nodes.
Dimitri Van De Ville Professor of Bioengineering, EPFL and University of Geneva
Dimitri Van De Ville received the Ph.D. degree in computer science engineering from Ghent University, Belgium, in 2002. He was a post-doctoral fellow (2002-2005) at the lab of Prof. Michael Unser at the Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland, before becoming responsible for the Signal Processing Unit at the University Hospital of Geneva, Switzerland, as part of the Centre d’Imagerie Biomédicale (CIBM). In 2009, he received a Swiss National Science Foundation professorship and since 2015 became Professor of Bioengineering at the EPFL, jointly affiliated with the University of Geneva, Switzerland. His main research interest is in computational neuroimaging to advance cognitive and clinical neurosciences. His methods toolbox includes wavelets, sparsity, deconvolution, graph signal processing. He was a recipient of the Pfizer Research Award 2012, the NARSAD Independent Investigator Award 2014, the Leenaards Foundation Award 2016, and was elected Fellow of the IEEE in 2020.
Dr. Van De Ville serves as an Editor for the new journal NEUROIMAGE: REPORTS since 2020, as a Senior Editor for the IEEE TRANSACTIONS ON SIGNAL PROCESSING since 2019 and as an Editor for the SIAM Journal on Imaging Science from 2018 on. He served as an Associate Editor for the IEEE TRANSACTIONS ON IMAGE PROCESSING from 2006 to 2009, the IEEE SIGNAL PROCESSING LETTERS from 2004 to 2006. He was the Chair of the Bio Imaging and Signal Processing (BISP) TC of the IEEE Signal Processing Society (2012-2013) and the Founding Chair of the EURASIP Biomedical Image & Signal Analytics SAT (2016-2018). He is Co-Chair of the biennial Wavelets & Sparsity series conferences, together with Y. Lu and M. Papadakis.
Two paradigms continue to spar in the neuroscience at the local and system levels. At the elemental level of neurons, and grounded in the prominent work of many cellular physiologists including Eccles, Hodgkin and Huxley, overwhelming evidence implicate directional flows of information from functional unit to functional unit. At another system level, and thrusted by giants of system Neuroscience like Freeman, Eckhorn, Gray and Singer, focus is shifted to ensemble activities that yield evidence of functional synchronization. In their extreme forms, both paradigms eschew one important property of complex functional systems. A strictly serial model of synaptic propagation labors to achieve mass action. And a completely collective system presents many roadblocks to a dynamics of its self-organized activities, making for a brain frozen in time and inefficient at adaptation and flexibility. I will place in the reconciliatory middle ground the theory of brain metastability initially pioneered by Kelso. Its spatiotemporal complexity is permissive of information flows at the same time as transient coordination provides collective power at multiple spatial scales. I will provide mathematical bases for its study in models that prepare for the empirical encounter of its phenomenology; I will outline empirical evidence of its pervasiveness. Although metastability is conceptually contiguous with the two aforementioned paradigms, I will describe the pitfalls that follow from analyzing it as approximations of them, and I will argue that a shift in perspective and methods is required to fully understand brain complexity.Recommended Articles:
Emmanuelle Tognoli Research Professor, Complex Systems and Brain Sciences, Florida Atlantic University
Dr. Tognoli is a Research Professor in Complex Systems and Brain Sciences at Florida Atlantic University. Her overarching scientific motivation is to understand brain function and dysfunction using the concepts and tools of complexity science. Her main research areas are spatiotemporal brain metastability, the neurophysiological basis of social behavior and the development of complex experimental systems for human-machine and neuro-technological interfaces. Her thinking has been enriched by numerous collaborations with psychiatrists, neurologists, neuropsychologists, ophthalmologists, physicists, mathematicians, behavioral and biological scientists, psychologists and engineers.