Post-traumatic stress disorder (PTSD) includes a constellation of disabling behavioral and emotional symptoms that occur in a proportion of individuals exposed to severe psychological trauma. This chapter reviews the structural neuroimaging findings pertaining to specific brain regions in adults with PTSD. Although the majority of adult neuroimaging reports have centered on the hippocampus, medial prefrontal cortex, and amygdala, structural studies are potential abnormalities in other brain regions as well. The cavum septum pelucidum (CSP), a small cerebrospinal fluid filled cleft in the anterior portion of the septo-callosal junction, has been found to exist with greater frequency in individuals diagnosed with PTSD. Pediatric studies of PTSD have not fully replicated findings reported in the adult literature, and suggest that the neuroanatomical correlates of PTSD may manifest in a more generalized manner in children and adolescents who are traumatized.

Pediatric neuroimaging techniques can probe the integrity of brain function and normal brain maturational processes and provide a window into possible abnormalities in neurocognitive development. This chapter describes the initial investigations and discusses what has been found regarding the changes in brain function that support the healthy maturation of cognitive control of behavior. Basic cognitive processes, which are evident in infancy and show dramatic changes throughout childhood, continue to develop throughout adolescence. Two higher-order cognitive abilities crucial to the voluntary control of behavior are working memory and voluntary suppression of context-inappropriate responses. Most pediatric functional magnetic resonance imaging (fMRI) studies are performed to assist in the localization of language areas to guide excision lesions to relieve epileptic seizures. Pediatric fMRI studies have provided insight into the possible factors underlying the etiology of developmental abnormalities such as attention-deficit hyperactivity disorder (ADHD) and dyslexia.