Dancing, it turns out, is good for more than your social life; it’s good for your brain. New York Times health columnist Gretchen Reynolds reports on a new study suggesting that social dancing, the kind that -like country dancing- requires many dancers to coordinate their steps and movement around a dance floor, –does some special things to our brains. Like what? Reynolds tells us that it appears to slow some unfortunate changes that almost inevitably affect aging brains, and by older, she means the brains of people over 40. The researchers, from the University of Illinois in Urbana and other schools, tested 174 healthy people in their 60s and 70s with no signs of cognitive impairment for their aerobic fitness and mental capacities. Then they randomly divided the volunteers into several groups. One group walked briskly three times a week; one did stretching and balancing exercises three times a week; and one group learned country dance three times a week, practicing intricate choreographies and moving from partner to partner. After six months, all volunteers were given brain scans, and all brains showed some normal degeneration of white matter in their fornix, a part of the brain involved with processing speed and memory. The dancers’ brains, however, showed something strange. Many actually had denser white matter than they had six months earlier, and Reynolds reports, were reflected in their cognitive performance.