Elementary school-age children who get less than nine hours of sleep per night have significant differences in certain brain regions responsible for memory, intelligence and well-being compared to those who get the recommended nine to 12 hours of sleep per night, according to a new study led by University of Maryland School of Medicine (UMSOM) researchers. Such differences correlated with greater mental health problems, like depression, anxiety, and impulsive behaviors, in those who lacked sleep. Inadequate sleep was also linked to cognitive difficulties with memory, problem solving and decision making. The findings were published today in the journal The Lancet Child & Adolescent Health.