Romantic breakups really can go right to ones head more specifically, to ones hippocampus.That part of the brain, which helps control memory and regulate emotion, tends to be smaller in people whove both experienced childhood trauma, then lived through the end of a long-term relationship once they are older, according to a study in the European Journal of Neuroscience.How Trauma Impacts the BrainA smaller hippocampus is a hallmark of many mental disorders. Although childhood mistreatment is a known risk factor for later psychological problems, a solid link between that and hippocampus size has never been solidified.To better understand the link between long ago trauma and more recent emotional crisis, researchers studied a group of 196 young adults. They completed surveys both about childhood trauma as well as more recent emotionally challenging experiences, including breakups. Then they performed magnetic resonance imaging (MRI) to study the hippocampus size.They found smaller hippocampus sizes in people who had both a troubled childhood and experienced a tough breakup. Childhood trauma alone seemed to have little to no effect on the adult hippocampus sizes. Other studies have also linked adult trauma to a smaller hippocampus.More Stressors, More ProblemsStudy author Henriette Acosta of the Philipps University of Marburg and University of Turku was interested in pursuing two lines of research at once. Some studies show that children experiencing abuse often develop coping strategies. But Acosta wanted to know if those strategies carried on into adulthood.Not only did the post-questionnaire MRIs show a link between childhood trauma, adult breakup and hippocampus size, it revealed a dose-response effect." In other words, study participants who rated themselves as experiencing a higher degree of childhood trauma and a later breakup had even smaller hippocampuses than those who reported a smaller level of trauma, as well as a breakup.Interestingly, participants who had reported childhood trauma but no breakup did not appear to have their hippocampuses affected much, if at all. The researchers speculate that may be a sign of resilience in some people.Although the study points out a possible link between trauma and hippocampus size, it doesnt firmly establish cause and effect. Also, asking subjects to report and rate childhood trauma can be subjective. Future studies that follow a larger group of people over a longer time period could better cement that link.Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:European Journal of Neuroscience. The association between childhood adversity and hippocampal volumes is moderated by romantic relationship experiencesBefore joining Discover Magazine, Paul Smaglik spent over 20 years as a science journalist, specializing in U.S. life science policy and global scientific career issues. He began his career in newspapers, but switched to scientific magazines. His work has appeared in publications including Science News, Science, Nature, and Scientific American.