A new study shows how our very short-term “working memory,” which allows the brain to stitch together sensory information, operates. The system retains a limited number of high-resolution images for a few seconds, rather than a wider range of fuzzier impressions. Humans rarely move their eyes smoothly. As our eyes flit from object to object, the visual system briefly shuts off to cut down visual “noise,” said one of the psychologists. So the brain gets a series of snapshots of about a quarter-second, separated by brief gaps.