The study by Carrion et al is a significant one. It showed that the environment can literally changed the anatomical structure of the brain. Chronic stress as shown in this study changed the size of the hippocampus, the major memory center of the brain or hard-drive. Children with the most severe PTSD (Post Traumatic Stress Disorder) showed reduction in the size of the hippocampus.
This might be the reason why many young children who experienced adverse events later on become depressed, drug addict, commit suicide, smoke, hypertensive, and become obese as an adult.
Lesson: All children should be exposed to PEACE -- Positive Environment Around Children Everyday.
Leo Leonidas, MD, FAAP, Bangor, Maine
PEDIATRICS 2007 Mar;119(3):509-16.
Stress predicts brain changes in children: a pilot longitudinal study on youth stress, posttraumatic stress disorder, and the hippocampus.
Carrion VG, Weems CF, Reiss AL.
Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California, USA. vcarrion@stanford.edu
OBJECTIVE: Does stress damage the brain? Studies of adults with posttraumatic stress disorder have demonstrated smaller hippocampal volumes when compared with the volumes of adults with no posttraumatic stress disorder. Studies of children with posttraumatic stress disorder have not replicated the smaller hippocampal findings in adults, which suggests that smaller hippocampal volume may be caused by neurodevelopmental experiences with stress. Animal research has demonstrated that the glucocorticoids secreted during stress can be neurotoxic to the hippocampus, but this has not been empirically demonstrated in human samples. We hypothesized that cortisol volumes would predict hippocampal volume reduction in patients with posttraumatic symptoms. PATIENTS AND METHODS: We report data from a pilot longitudinal study of children (n = 15) with history of maltreatment who underwent clinical evaluation for posttraumatic stress disorder, cortisol, and neuroimaging. RESULTS: Posttraumatic stress disorder symptoms and cortisol at baseline predicted hippocampal reduction over an ensuing 12- to 18-month interval. CONCLUSIONS: Results from this pilot study suggest that stress is associated with hippocampal reduction in children with posttraumatic stress disorder symptoms and provide preliminary human evidence that stress may indeed damage the hippocampus. Additional studies seem to be warranted.