Reduced Hippocampal Activity in Youth with Posttraumatic Stress Symptoms: An fMRI Study

Objective Youth who experience interpersonal trauma and have posttraumatic stress symptoms (PTSS) develop cognitive deficits that impact their development. Our goal is to investigate the function of the hippocampus in adolescents with PTSS during a memory processing task. Methods Twenty-seven adolescents between the ages of 10-17 years (16 with PTSS and 11 healthy controls) encoded and retrieved visually presented nouns (Verbal Declarative Memory Task) while undergoing fMRI scanning. Results The PTSS group demonstrated reduced activation of the right hippocampus during the retrieval component of the task. Further, severity of symptoms of avoidance and numbing correlated with reduced left hippocampal activation during retrieval. Conclusions Decreased activity of the hippocampus during a verbal memory task may be a neurofunctional marker of PTSS in youth with history of interpersonal trauma. The results of this study may facilitate the development of focused treatments and may be of utility when assessing treatment outcome for PTSS.