David C. Van Essen (born September 14, 1945) is an American neuroscientist specializing in neurobiology and studies the structure, function, development, connectivity and evolution of the cerebral cortex of humans and nonhuman relatives. [1] After over two decades of teaching at the Washington University in St. Louis School of Medicine, he currently serves as an Alumni Endowed Professor of Neuroscience and maintains an active laboratory. Van Essen has held numerous positions, including Editor-in-Chief of the Journal of Neuroscience, Secretary of the Society for Neuroscience, and the President of the Society for Neuroscience from 2006 to 2007. Additionally, Van Essen has received numerous awards for his efforts in education and science, including the Krieg Cortical Discoverer Award from the Cajal Club in 2002, the Peter Raven Lifetime Achievement Award from St. Louis Academy of Science in 2007, and the Second Century Award in 2015 and the Distinguished Educator Award in 2017, both from Washington University School of Medicine. [2] [3]
A key contributor to the understanding of the primate visual system, he created one of the most well-known [4] maps of the visual pathway in the primate cortex with Dr. Daniel J. Felleman, [5] based on anatomical tracing. This study laid the groundwork for understanding cortical systems in general as hierarchical circuits. [6]
Van Essen received his undergraduate degree in chemistry in 1967 from The California Institute of Technology, working on the leech nervous system with John Nichols. He received his doctoral degree in Neurobiology in 1971 from Harvard University and continued as a postdoctoral fellow at Harvard University under David H. Hubel and Torsten Wiesel where they studied the visual cortex of cats. [7] This experience led Van Essen to study visual systems. Van Essen continued to pursue additional postdoctoral work at the University of Oslo and at University College London [8] where he studied the visual cortex of monkeys and developed a "pencil and tracing paper" method to make 2D cortical flat maps. [7]
Following his postdoctoral education, David Van Essen joined the faculty at The California Institute of Technology in 1976. [1] Following his time at Caltech, Van Essen then moved to Washington University in St. Louis in 1992, where he served as the Head of the Department of Anatomy and Neurobiology for two decades. [2] Van Essen stepped down from this position in 2012. His earlier research included studies of simpler systems, including synapse elimination at the neuromuscular junction. Van Essen has hypothesized that tension along axons and dendrites accounts for many aspects of morphogenesis, including how and why the cortex gets its folds and how cortical folding abnormalities arise in brain disorders.
Van Essen is employed at Washington University in St. Louis and manages a lab that examines the structure, function, connectivity, development, and evolution of the cerebral cortex in both humans and primates. [1] His current research focuses primarily on cortical structure and function in disease models, such as autism, schizophrenia, and William Syndrome. [9] With the use of neuroanatomical data collected through collaboration by Washington University and other private institutions, Van Essen's research has enhanced the development and utilization of different methods used in computerized brain mapping and neuroinformatics to enhance data findings and analysis. While Van Essen's cortical cartography methods began with manually-generated maps, this area of research has developed into the novel usage of software tools for brain visualization.
David Van Essen also led the Human Connectome Project (HCP) as the Principal Investigator together with Co-Principal Investigator Kamil Ugurbil; HCP is a 5-year project designed to map the human brain circuitry. [2] This project uses various methods, such as structural and functional imaging methods, to analyze parcellation and connectivity of both human and nonhuman brains. Through the usage of over 1,200 brain models, the project allows researchers to relate their findings to behavioral phenotypes and genetic markers. [2] Most recently, in collaboration with the HCP, the Van Essen lab has identified many visual areas in the macaque monkey and has characterized a novel parcellation of the human neocortex. This research has greatly advanced the current understanding of the hierarchical organization of the brain. Additionally, with a leading role in the HCP's development, the Van Essen lab is creating a Connectome Workbench for data to be freely available and stored.
Van Essen's laboratory also collaborates with Terrie Inder, Jeff Neil, Jason Hill, and other affiliates to conduct research on human cortical development. Here, the research team studies human cortical development in premature and mature infants to analyze normal cortical maturation and find cortical abnormalities that correspond to childhood developmental abnormalities. Additionally, Van Essen and his team have developed a data mining resource called SumsDB. This database, which features an extensive and accessible data repository, includes freely available results from both PET and fMRI scans. [2]
David Van Essen's contributions towards the neurobiology field focus on the central nervous system as well as data sharing. His contributions to the Human Connectome Project provides the mapping of the brain and widespread sharing of the project to promote neuroinformatics. More specifically, the Connectome Workbench has provided a user-friendly platform in order to access various levels of data. Furthermore, while participating in the Society for Neuroscience, Van Essen contributed to the Neuroinformatics Committee. [10] While the committee existed only five years, the subfield continues to grow in recognition and importance. Van Essen has contributed to mapping cortical convolutions; first by hand, then computerizing the process leading to the development of computerized cortical cartography. [2] [3]
David Van Essen's most cited publications are referenced below:
The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and then reaches the visual cortex. The area of the visual cortex that receives the sensory input from the lateral geniculate nucleus is the primary visual cortex, also known as visual area 1 (V1), Brodmann area 17, or the striate cortex. The extrastriate areas consist of visual areas 2, 3, 4, and 5.
A cortical minicolumn (also called cortical microcolumn) is a vertical column through the cortical layers of the brain. Neurons within the microcolumn "receive common inputs, have common outputs, are interconnected, and may well constitute a fundamental computational unit of the cerebral cortex". Minicolumns comprise perhaps 80–120 neurons, except in the primate primary visual cortex (V1), where there are typically more than twice the number. There are about 2×108 minicolumns in humans. From calculations, the diameter of a minicolumn is about 28–40 μm. Minicolumns grow from progenitor cells within the embryo and contain neurons within multiple layers (2–6) of the cortex.
A cortical column is a group of neurons forming a cylindrical structure through the cerebral cortex of the brain perpendicular to the cortical surface. The structure was first identified by Mountcastle in 1957. He later identified minicolumns as the basic units of the neocortex which were arranged into columns. Each contains the same types of neurons, connectivity, and firing properties. Columns are also called hypercolumn, macrocolumn, functional column or sometimes cortical module. Neurons within a minicolumn (microcolumn) encode similar features, whereas a hypercolumn "denotes a unit containing a full set of values for any given set of receptive field parameters". A cortical module is defined as either synonymous with a hypercolumn (Mountcastle) or as a tissue block of multiple overlapping hypercolumns.
Ocular dominance columns are stripes of neurons in the visual cortex of certain mammals that respond preferentially to input from one eye or the other. The columns span multiple cortical layers, and are laid out in a striped pattern across the surface of the striate cortex (V1). The stripes lie perpendicular to the orientation columns.
Supplementary eye field (SEF) is the name for the anatomical area of the dorsal medial frontal lobe of the primate cerebral cortex that is indirectly involved in the control of saccadic eye movements. Evidence for a supplementary eye field was first shown by Schlag, and Schlag-Rey. Current research strives to explore the SEF's contribution to visual search and its role in visual salience. The SEF constitutes together with the frontal eye fields (FEF), the intraparietal sulcus (IPS), and the superior colliculus (SC) one of the most important brain areas involved in the generation and control of eye movements, particularly in the direction contralateral to their location. Its precise function is not yet fully known. Neural recordings in the SEF show signals related to both vision and saccades somewhat like the frontal eye fields and superior colliculus, but currently most investigators think that the SEF has a special role in high level aspects of saccade control, like complex spatial transformations, learned transformations, and executive cognitive functions.
Brain mapping is a set of neuroscience techniques predicated on the mapping of (biological) quantities or properties onto spatial representations of the brain resulting in maps.
The inferior temporal gyrus is one of three gyri of the temporal lobe and is located below the middle temporal gyrus, connected behind with the inferior occipital gyrus; it also extends around the infero-lateral border on to the inferior surface of the temporal lobe, where it is limited by the inferior sulcus. This region is one of the higher levels of the ventral stream of visual processing, associated with the representation of objects, places, faces, and colors. It may also be involved in face perception, and in the recognition of numbers and words.
FreeSurfer is a brain imaging software package originally developed by Bruce Fischl, Anders Dale, Martin Sereno, and Doug Greve. Development and maintenance of FreeSurfer is now the primary responsibility of the Laboratory for Computational Neuroimaging at the Athinoula A. Martinos Center for Biomedical Imaging. FreeSurfer contains a set of programs with a common focus of analyzing magnetic resonance imaging (MRI) scans of brain tissue. It is an important tool in functional brain mapping and contains tools to conduct both volume based and surface based analysis. FreeSurfer includes tools for the reconstruction of topologically correct and geometrically accurate models of both the gray/white and pial surfaces, for measuring cortical thickness, surface area and folding, and for computing inter-subject registration based on the pattern of cortical folds.
Pasko Rakic is a Yugoslav-born American neuroscientist, who presently works in the Yale School of Medicine Department of Neuroscience in New Haven, Connecticut. His main research interest is in the development and evolution of the human brain. He was the founder and served as Chairman of the Department of Neurobiology at Yale, and was founder and Director of the Kavli Institute for Neuroscience. He is best known for elucidating the mechanisms involved in development and evolution of the cerebral cortex. In 2008, Rakic shared the inaugural Kavli Prize in Neuroscience. He is currently the Dorys McConell Duberg Professor of Neuroscience, leads an active research laboratory, and serves on Advisory Boards and Scientific Councils of a number of Institutions and Research Foundations.
In cognitive neuroscience, visual modularity is an organizational concept concerning how vision works. The way in which the primate visual system operates is currently under intense scientific scrutiny. One dominant thesis is that different properties of the visual world require different computational solutions which are implemented in anatomically/functionally distinct regions that operate independently – that is, in a modular fashion.
The retrosplenial cortex (RSC) is a cortical area in the brain comprising Brodmann areas 29 and 30. It is secondary association cortex, making connections with numerous other brain regions. The region's name refers to its anatomical location immediately behind the splenium of the corpus callosum in primates, although in rodents it is located more towards the brain surface and is relatively larger. Its function is currently not well understood, but its location close to visual areas and also to the hippocampal spatial/memory system suggest it may have a role in mediating between perceptual and memory functions, particularly in the spatial domain. However, its exact contribution to either space or memory processing has been hard to pin down.
A connectome is a comprehensive map of neural connections in the brain, and may be thought of as its "wiring diagram". An organism's nervous system is made up of neurons which communicate through synapses. A connectome is constructed by tracing the neuron in a nervous system and mapping where neurons are connected through synapses.
Connectomics is the production and study of connectomes: comprehensive maps of connections within an organism's nervous system. More generally, it can be thought of as the study of neuronal wiring diagrams with a focus on how structural connectivity, individual synapses, cellular morphology, and cellular ultrastructure contribute to the make up of a network. The nervous system is a network made of billions of connections and these connections are responsible for our thoughts, emotions, actions, memories, function and dysfunction. Therefore, the study of connectomics aims to advance our understanding of mental health and cognition by understanding how cells in the nervous system are connected and communicate. Because these structures are extremely complex, methods within this field use a high-throughput application of functional and structural neural imaging, most commonly magnetic resonance imaging (MRI), electron microscopy, and histological techniques in order to increase the speed, efficiency, and resolution of these nervous system maps. To date, tens of large scale datasets have been collected spanning the nervous system including the various areas of cortex, cerebellum, the retina, the peripheral nervous system and neuromuscular junctions.
The Human Connectome Project (HCP) is a five-year project sponsored by sixteen components of the National Institutes of Health, split between two consortia of research institutions. The project was launched in July 2009 as the first of three Grand Challenges of the NIH's Blueprint for Neuroscience Research. On September 15, 2010, the NIH announced that it would award two grants: $30 million over five years to a consortium led by Washington University in St. Louis and the University of Minnesota, with strong contributions from University of Oxford (FMRIB) and $8.5 million over three years to a consortium led by Harvard University, Massachusetts General Hospital and the University of California Los Angeles.
The Computation and Neural Systems (CNS) program was established at the California Institute of Technology in 1986 with the goal of training Ph.D. students interested in exploring the relationship between the structure of neuron-like circuits/networks and the computations performed in such systems, whether natural or synthetic. The program was designed to foster the exchange of ideas and collaboration among engineers, neuroscientists, and theoreticians.
The Karl Spencer Lashley Award is awarded by The American Philosophical Society as a recognition of research on the integrative neuroscience of behavior. The award was established in 1957 by a gift from Dr. Karl Spencer Lashley.
Randy L. Buckner is an American neuroscientist and psychologist whose research focuses on understanding how large-scale brain circuits support mental function and how dysfunction arises in illness.
Neural circuit reconstruction is the reconstruction of the detailed circuitry of the nervous system of an animal. It is sometimes called EM reconstruction since the main method used is the electron microscope (EM). This field is a close relative of reverse engineering of human-made devices, and is part of the field of connectomics, which in turn is a sub-field of neuroanatomy.
Anna Wang Roe is an American neuroscientist, the director of the Interdisciplinary Institute of Neuroscience and Technology (ZIINT), and full-time professor at the Zhejiang University, Hangzhou, China. She is known for her studies on the functional organization and connectivity of cerebral cortex and for bringing interdisciplinary approaches to address questions in systems neuroscience.