Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Map IDs the Core of the Human Brain

02.07.2008
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.

In this new study, a team of neuroimaging researchers led by Hagmann used state-of-the-art diffusion MRI technology, which is a non-invasive scanning technique that estimates fiber connection trajectories based on gradient maps of the diffusion of water molecules through brain tissue. A highly sensitive variant of the method, called diffusion spectrum imaging (DSI), can depict the orientation of multiple fibers that cross a single location. The study applies this technique to the entire human cortex, resulting in maps of millions of neural fibers running throughout this highly furrowed part of the brain.

Sporns then carried out a computational analysis trying to identify regions of the brain that played a more central role in the connectivity, serving as hubs in the cortical network. Surprisingly, these analyses revealed a single highly and densely connected structural core in the brain of all participants.

"We found that the core, the most central part of the brain, is in the medial posterior portion of the cortex, and it straddles both hemispheres," Sporns said. "This wasn't known before. Researchers have been interested in this part of the brain for other reasons. For example, when you're at rest, this area uses up a lot of metabolic energy, but until now it hasn't been clear why."

The researchers then asked whether the structural connections of the brain in fact shape its dynamic activity, Sporns said. The study examined the brains of five human participants who were imaged using both fMRI and DSI techniques to compare how closely the brain activity observed in the fMRI mapped to the underlying fiber networks.

"It turns out they're quite closely related," Sporns said. "We can measure a significant correlation between brain anatomy and brain dynamics. This means that if we know how the brain is connected we can predict what the brain will do."

Sporns said he and Hagmann plan to look at more brains soon, to map brain connectivity as brains develop and age, and as they change in the course of disease and dysfunction.

The study can be viewed at http://www.plos.org/press/plbi-06-07-sporns.pdf. After the embargo, the study can be viewed at http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0060159.

The study was supported in part by the J.S. McDonnell Foundation, the University of Lausanne, Center for Biomedical Imaging (CIBM) of the Geneva-Lausanne Universities, Ecole Polytechnique Fédérale de Lausanne and the National Institutes of Health.

Sporns can be reached at osporns@indiana.edu or 812-855-2772. To speak with Hagmann, contact Patric.hagmann@epfl.ch.

Tracy James | newswise
Further information:
http://www.indiana.edu

More articles from Health and Medicine:

nachricht How prenatal maternal infections may affect genetic factors in Autism spectrum disorder
22.03.2017 | University of California - San Diego

nachricht Camouflage apples
22.03.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Pulverizing electronic waste is green, clean -- and cold

22.03.2017 | Materials Sciences

Astronomers hazard a ride in a 'drifting carousel' to understand pulsating stars

22.03.2017 | Physics and Astronomy

New gel-like coating beefs up the performance of lithium-sulfur batteries

22.03.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>