Objective Index of Sleep Fragmentation Correlates With Smaller Hippocampi in Posttraumatic Stress Disorder

Sleep disruption in posttraumatic stress disorder (PTSD) manifests as fragmented night-time sleep due to insomnia and nightmares. Animal research and clinical studies of primary insomnia suggest that sleep fragmentation is associated with smaller hippocampi, but a study in PTSD found no significant association between subjective sleep quality and hippocampus volume. We examined an objective, actigraphy measure of sleep fragmentation in relation to hippocampus volumes in adults with PTSD.