News from the American Academy of Pediatrics:

Tics are more common in children than previously thought. In a new study, researchers observed more than 500 schoolchildren over an eight-month period. They found that at least once, almost a quarter of the children had a motor tic — such as an abnormal shoulder shrug, eye blink or facial grimace. Most of the tics were mild, observed on only one occasion, and were not accompanied by problem behaviors. In addition, the researchers witnessed more tics over the winter months — although it's not clear why that was.