Body & Brain

Viral link to chronic fatigue nixed
A 2009 finding of a mouse virus called XMRV in chronic fatigue patients (SN: 11/7/09, p. 13) might have stemmed from tainted laboratory compounds. In two studies published online May 31 in Science, two separate teams of U.S. scientists report that those earlier findings appear to  have arisen because lab reagents and cell lines used in the analysis were contaminated with the virus. One of the teams also finds no evidence of XMRV in the blood of chronic fatigue patients, including dozens who had been found to have the virus in the 2009 study, which was done by a different group.  The cause of chronic fatigue syndrome remains unknown, authors of the new studies argue. —Nathan Seppa

Colored lenses for migraines
Tinted glasses specially made for an individual with migraines can help to alleviate some kinds of migraine discomfort, researchers report in an upcoming issue of Cephalalgia. Michigan State University scientists led a team that used magnetic resonance imaging of the brain to establish an optimal hue for each of 11 migraine patients, tints that best reduced the image distortion for each patient. Next, the participants viewed striped, intense patterns known to trigger brain hyperactivation. MRI scans revealed that proper tinting lessened the discomfort when viewing such images and also during routine viewing. The findings suggest that precise tints work by calming overactivation in the visual cortex of the brain. —Nathan Seppa

HDL drug trial halted
The National Institutes of Health announced May 26 that it has stopped a medical trial of high-dose niacin, or vitamin B3, which was being tested for its ability to increase HDL, the good cholesterol. All participants in a trial of more than 3,400 people were assigned to take a cholesterol-lowering drug called a statin. Roughly half also got niacin. After 32 months of follow-up, those on niacin showed gains in HDL and decreased triglycerides in the blood — both promising changes. But those people fared no better against heart attacks or strokes than did the statin-only group. —Nathan Seppa

Getting closer to mind reading
With a brain scan, scientists can tell what a person is thinking (as long as they’re thinking about math, their day, a song or nothing). In a new study, subjects thought about their day, subtracted numbers, silently sang lyrics to their favorite song or rested quietly while they underwent an fMRI scan. Scientists then collected the signals generated by the different brain states and analyzed activity patterns across many different parts of the brain, rather than individual regions. Researchers correctly identified which mental task a new set of participants was doing 84 percent of the time just by looking at scans, Stanford University School of Medicine researchers report in an upcoming Cerebral Cortex. The technology might lead to diagnostic tests for disorders in which brain networks are disrupted, such as Alzheimer’s disease or autism. —Laura Sanders

Love is a powerful drug
Single prairie voles are more likely than partnered voles to succumb to drug addiction. Though social bonds in people are thought to be protective against addiction, just how that protection happens has been a mystery. Male prairie voles in a monogamous relationship eschew amphetamine, while single males found it strongly rewarding, researchers led by Zuoxin Wang of Florida State University in Tallahassee report. In both groups, amphetamine caused nerve cells to release the feel-good messenger dopamine. In single voles, this dopamine latched on to proteins on other nerve cells, but in partnered voles, it didn’t. This opposite reaction might explain why social relationships protect against drug addiction, the researchers propose in the June 1 Journal of Neuroscience. —Laura Sanders