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Brain networks may avoid traffic jams at their busiestintersections by communicating on different frequencies,researchers at Washington University School of Medicine in St.Louis, the University Medical Center at Hamburg-Eppendorf and theUniversity of Tubingen have learned. "Many neurological and psychiatric conditions are likely to involveproblems with signaling in brain networks," says co-author MaurizioCorbetta, MD, the Norman J. Stupp Professor of Neurology atWashington University. "Examining the temporal structure of brainactivity from this perspective may be especially helpful inunderstanding psychiatric conditions like depression and schizophrenia , where structural markers are scarce." The research was published in Nature Neuroscience. Scientists usually study brain networks - areas of the brain thatregularly work together - using magnetic resonance imaging, whichtracks blood flow. They assume that an increase in blood flow topart of the brain indicates increased activity in the brain cellsof that region. "Magnetic resonance imaging is a useful tool, but it does havelimitations," Corbetta says. "It only allows us to track brain cellactivity indirectly, and it is unable to track activity that occursat frequencies greater than 0.1 hertz, or once every 10 seconds. Weknow that some signals in the brain can cycle as high as 500 hertz,or 500 times per second." For the new study, conducted at the University Medical Center atHamburg-Eppendorf, the researchers used a technique calledmagnetoencephalography (MEG) to analyze brain activity in 43healthy volunteers. MEG detects very small changes in magneticfields in the brain that are caused by many cells being active atonce. It can detect these signals at rates up to 100 hertz. "We found that different brain networks ticked at differentfrequencies, like clocks ticking at different speeds," says leadauthor Joerg Hipp, PhD, of the University Medical Center atHamburg-Eppendorf and the University of T bingen, both in Germany. For example, networks that included the hippocampus, a brain areacritical for memory formation, tended to be active at frequenciesaround 5 hertz. Networks constituting areas involved in the sensesand movement were active between 32 hertz and 45 hertz. Many otherbrain networks were active at frequencies between eight and 32hertz. These "time-dependent" networks resemble different airlineroute maps, overlapping but each ticking at a different rate. "There have been a number of fMRI studies of depression andschizophrenia showing 'spatial' changes in the organization ofbrain networks," Corbettta says. "MEG studies provide a window intoa much richer 'temporal' structure. In the future, this might offernew diagnostic tests or ways to monitor the efficacy ofinterventions in these debilitating mental conditions." Additional References Citations. I am an expert from laseriplmachine.com, while we provides the quality product, such as Ultrasound Fat Burning Machine , Laser Tattoo Removal Machine, Laser IPL Machine,and more.
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