People who say they are insomniacs have problems focusing during the day and may have misconceptions about the quality of their sleep, according to findings published in the journal Sleep. Researchers at the University of California at San Diego, compared brain scans of self-described insomniacs with those who say they sleep well while they performed memory tests. The results showed that insomniacs' brains functioned less efficiently. A sleep researcher in the U.K. found that each group's sleep quality was similar. "Maybe they're perceiving what happened in the night differently; maybe what is affecting their working memory and ability to focus on the task at hand is also causing insomnia," said Neil Stanley.