Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Technique Developed At UCSD For Deciphering

15.06.2004


A team led by University of California San Diego neurobiologists has developed a new approach to interpreting brain electroencephalograms, or EEGs, that provides an unprecedented view of thought in action and has the potential to advance our understanding of disorders like epilepsy and autism.


Image of the brain with colored spheres indicating clusters of activity
Photo Credit: Scott Makeig



The new information processing and visualization methods that make it possible to follow activation in different areas of the brain dynamically are detailed in a paper featured on the cover of the June 15 issue of the journal Public Library of Science Biology (plos.org) The significance of the advance is that thought processes occur on the order of milliseconds—thousandths of a second—but current brain imaging techniques, such as functional Magnetic Resonance Imaging and traditional EEGs, are averaged over seconds. This provides a “blurry” picture of how the neural circuits in the brain are activated, just as a picture of waves breaking on the shore would be a blur if it were created from the average of multiple snapshots.

“Our paper is the culmination of eight years of work to find a new way to parse EEG data and identify the individual signals coming from different areas of the brain,” says lead author Scott Makeig, a research scientist in UCSD’s Swartz Center for Computational Neuroscience of the Institute for Neural Computation. “This much more comprehensive view of brain dynamics was only made possible by exploiting recent advances in mathematics and increases in computing power. We expect many clinical applications to flow from the method and have begun collaborations to study patients with epilepsy and autism.”


To take an EEG, recording electrodes—small metal disks—are attached to the scalp. These electrodes can detect the tiny electrical impulses nerve cells in the brain send to communicate with each other. However, interpreting the pattern of electrical activity recorded by the electrodes is complicated because each scalp electrode indiscriminately sums all of the electrical signals it detects from the brain and non-brain sources, like muscles in the scalp and the eyes.

“The challenge of interpreting an EEG is that you have a composite of signals from all over the brain and you need to find out what sources actually contributed to the pattern,” explains Makeig. “It is a bit like listening in on a cocktail party and trying to isolate the sound of each voice. We found that it is possible, using a mathematical technique called Independent Component Analysis, to separate each signal or “voice” in the brain by just treating the voices as separate sources of information, but without other prior knowledge about each voice.”

Independent component analysis, or ICA, looks at the distinctiveness of activity in each patch of the brain’s cortex. It uses this information to determine the location of the patch and separate out the signals from non-brain sources. Because ICA can distinguish signals that are active at the same time, it makes it possible to identify the electrical signals in the brain that correspond to the brain telling the muscles to take an action —which in the paper was deciding whether or not to press a button in response to an image flashed on a computer screen—and to separate this signal from the signals the brain uses to evaluate the consequences of that action.

According to Makeig, UCSD was a leader in developing the earlier methods of interpreting EEGs forty years ago. “The new, more general ’ICA’ method continues this tradition of UCSD excellence in cognitive electrophysiology research,” he says.

The coauthors on the paper, in addition to Makeig, include Arnaud Delorme and Tzyy-Ping Jung, Swartz Center for Computational Neuroscience; Marissa Westerfield and Jeanne Townsend, UCSD’s Department of Neurosciences; Eric Courchesne, Children’s Hospital Research Center and UCSD’s Department of Neurosciences; and Terrence Sejnowski, UCSD professor of biology and Howard Hughes Medical Institute professor at the Swartz Center for Computational Neuroscience and the Salk Institute for Biological Studies. The study was funded by the Swartz Foundation, the National Institutes of Health and the Howard Hughes Medical Institute.

Sherry Seethaler | University of California
Further information:
http://ucsdnews.ucsd.edu/newsrel/science/sneweegs.asp

More articles from Life Sciences:

nachricht Colorectal cancer: Increased life expectancy thanks to individualised therapies
20.02.2020 | Christian-Albrechts-Universität zu Kiel

nachricht Sweet beaks: What Galapagos finches and marine bacteria have in common
20.02.2020 | Max-Planck-Institut für Marine Mikrobiologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A step towards controlling spin-dependent petahertz electronics by material defects

The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.

Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...

Im Focus: Freiburg researcher investigate the origins of surface texture

Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.

Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...

Im Focus: Skyrmions like it hot: Spin structures are controllable even at high temperatures

Investigation of the temperature dependence of the skyrmion Hall effect reveals further insights into possible new data storage devices

The joint research project of Johannes Gutenberg University Mainz (JGU) and the Massachusetts Institute of Technology (MIT) that had previously demonstrated...

Im Focus: Making the internet more energy efficient through systemic optimization

Researchers at Chalmers University of Technology, Sweden, recently completed a 5-year research project looking at how to make fibre optic communications systems more energy efficient. Among their proposals are smart, error-correcting data chip circuits, which they refined to be 10 times less energy consumptive. The project has yielded several scientific articles, in publications including Nature Communications.

Streaming films and music, scrolling through social media, and using cloud-based storage services are everyday activities now.

Im Focus: New synthesis methods enhance 3D chemical space for drug discovery

After helping develop a new approach for organic synthesis -- carbon-hydrogen functionalization -- scientists at Emory University are now showing how this approach may apply to drug discovery. Nature Catalysis published their most recent work -- a streamlined process for making a three-dimensional scaffold of keen interest to the pharmaceutical industry.

"Our tools open up whole new chemical space for potential drug targets," says Huw Davies, Emory professor of organic chemistry and senior author of the paper.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

70th Lindau Nobel Laureate Meeting: Around 70 Laureates set to meet with young scientists from approx. 100 countries

12.02.2020 | Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

 
Latest News

Active droplets

21.02.2020 | Medical Engineering

Finding new clues to brain cancer treatment

21.02.2020 | Health and Medicine

Beyond the brim, Sombrero Galaxy's halo suggests turbulent past

21.02.2020 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>