Psychologists at the University of Tulsa are looking into what causes nightmares and giving children the brain power to make them go away, reports KJRH.

“Nightmares can be caused by anxiety, by stress,” Lisa Cromer, an associate professor of psychology at TU, said. “Sometimes kids will have nightmares on Sunday when they know they’ve got school the next day.”

Cromer said recurring nightmares can cause physical and mental health issues, which is why she and a team of doctoral students are studying the effects of nightmares in children and how to get rid of them.