Parents may feel it’s clear that missing a nap means their young children will be grumpy and out-of-sorts, but scientists who study sleep say almost nothing is known about how daytime sleep affects children’s coping skills and learning. Now neuroscientist Rebecca Spencer at the University of Massachusetts Amherst has received a five-year, $2 million grant from NIH’s Heart, Lung and Blood Institute to significantly advance knowledge about how napping and sleep affect memory, behavior and emotions in preschoolers.