Here are excerpts from three different stories from this morning's news.
Telegraph UK - Scientist identify brain 'core' that could reveal secrets of thought
After centuries searching for the seat of consciousness, scientists have identified a good place to look.
A "core" region of the brain has been identified by an international team which has produced the first complete high-resolution map of the human cerebral cortex, the wrinkly surface of the brain where awareness, thought and other features of high level thinking reside.
The team traced the connections between millions of brain cells and identified a highly connected single network core, or hub, that may be key to the workings of both hemispheres of the brain.The work by the researchers from Indiana University, University of Lausanne, Switzerland, Ecole Polytechnique Fédérale de Lausanne, Switzerland, and Harvard Medical School marks a major step in understanding the most complicated and mysterious organ in the universe.
They believe the discovery will be an invaluable tool for interpreting brain scans and understanding the brain. As for consciousness, that quest will have to wait until neuroscientists can agree on a precise definition of what they are talking about.
The study not only provides a comprehensive map of brain connections (the brain "connectome"), but also describes a novel application of a non-invasive technique that can be used by other scientists to continue mapping the trillions of neural connections in the brain at even greater resolution, which is becoming a new field of science termed "connectomics."
Indiana University Press Release - New map IDs the core of the human brain
BLOOMINGTON, Ind. -- An international team of researchers has created the first complete high-resolution map of how millions of neural fibers in the human cerebral cortex -- the outer layer of the brain responsible for higher level thinking -- connect and communicate. Their groundbreaking work identified a single network core, or hub, that may be key to the workings of both hemispheres of the brain.The work by the researchers from Indiana University, University of Lausanne, Switzerland, Ecole Polytechnique Fédérale de Lausanne, Switzerland, and Harvard Medical School marks a major step in understanding the most complicated and mysterious organ in the human body. It not only provides a comprehensive map of brain connections (the brain "connectome"), but also describes a novel application of a non-invasive technique that can be used by other scientists to continue mapping the trillions of neural connections in the brain at even greater resolution, which is becoming a new field of science termed "connectomics."
"This is one of the first steps necessary for building large-scale computational models of the human brain to help us understand processes that are difficult to observe, such as disease states and recovery processes to injuries," said Olaf Sporns, co-author of the study and neuroscientist at Indiana University.
The findings appear in the journal PLoS Biology today (June 30). Co-authors include Patric Hagmann and Reto Meuli, University Hospital Center and University of Lausanne; Leila Cammoun and Xavier Gigandet, Ecole Polytechnique Fédérale de Lausanne; Van J. Wedeen, Massachusetts General Hospital and Harvard Medical Center; and Christopher J. Honey, IU.
Until now, scientists have mostly used functional magnetic resonance imaging (fMRI) technology to measure brain activity -- locating which parts of the brain become active during perception or cognition -- but there has been little understanding of the role of the underlying anatomy in generating this activity. What is known of neural fiber connections and pathways has largely been learned from animal studies, and so far, no complete map of brain connections in the human brain exists.
New York Times - Scientists Identify the Brain’s Activity Hub
The outer layer of the brain, the reasoning, planning and self-aware region known as the cerebral cortex, has a central clearinghouse of activity below the crown of the head that is widely connected to more-specialized regions in a large network similar to a subway map, scientists reported Monday.
The new report, published in the free-access online journal PLoS Biology, provides the most complete rough draft to date of the cortex’s electrical architecture, the cluster of interconnected nodes and hubs that help guide thinking and behavior. The paper also provides a striking demonstration of how new imaging techniques focused on the brain’s white matter — the connections between cells, rather than the neurons themselves — are filling in a dimension of human brain function that has been all but dark.
In previous studies, scientists have used magnetic resonance imaging to identify peaks and valleys of neural activity when people are doing various things, like making decisions, reacting to frightening images or reliving painful memories. But these studies, while provocative, revealed virtually nothing about the underlying neural networks involved — about which brain regions speak to one another and when. Previous estimates of network structure, based on such imaging, have been sketchy.
The new findings, while not conclusive, give scientists what is essentially a wiring diagram that they can test and refine.
“This is just about the coolest paper I’ve seen in a long time, and forward-looking in terms of where the science is going,” said Dr. Marcus E. Raichle, a professor of neurology and radiology at Washington University in St. Louis, who was not involved in the research. He added, “They’ve found in the brain what looks like a hub map of the airline system for the United States.”
In the study, a collaboration that included the University of Lausanne in Switzerland, Harvard and Indiana University, researchers studied the brains of five healthy male volunteers using a new technique called diffusion spectrum imaging. The technique allows scientists to estimate the density and orientation of the connections running through specific brain locations. Using a computer analysis of the results, the researchers ranked the busiest spots on the cortex in order, by the number of connections they had. Finally, they plotted those spots back onto the brain maps of the five volunteers.
The hubs clustered in each man’s brain, in a region about the size of a palm, were centered atop the cortex like a small skullcap. “We haven’t had a comprehensive map of the brain showing what is connected to what, and you really need the whole thing before you can ask certain questions, like what happens if activity is clogged up at one of the hubs? How does that effect function?” said Olaf Sporns, a psychologist at Indiana University and the senior author of the paper. His co-authors were Patric Hagmann, Leila Cammoun, Xavier Gigandet, Reto Meuli, Christopher J. Honey and Van J. Wedeen.
To check their findings, the researchers performed a standard functional M.R.I. scan on the participants, measuring which areas of their gray matter — which bundles of their brain cells — were most active when the men were at rest. Sure enough, the same areas overlapped with the network hubs that the group had already identified. In previous studies, activation in these areas has been associated with wandering thought and acute self-awareness. In the jargon of the field, these areas “run hot” continuously during waking hours and consume far more energy than more peripheral areas.
Dr. Sporns said continued research should help produce a complete and detailed neural wiring diagram, what he called the “connectome” of the brain. “We hope we can get to a place where we have, in effect, a brain simulator, in the same way we have computer models that can simulate the climate,” he said, “so we can simulate activation patterns we see in clinical cases,” like psychiatric problems and brain injuries.
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