Studies show that early childhood abuse has causative long-term effects on brain areas involved in memory and emotion, including the hippocampus, amygdala and medial prefrontal cortex. Brain circuits mediating the stress response including norepinephrine neurons, and the hypothalamic-pituitary-adrenal (HPA) axis also play a role. This chapter presents post-traumatic stress disorder (PTSD), and a working model for a neural circuitry. It discusses relevant findings from the neuroimaging and stress hormone literature concerning patients who have experienced childhood abuse. The chapter addresses the issue of causation in reference to epidemiological studies and neuropsychiatric investigations. There is considerable interest in alterations in memory function of patients with childhood abuse-related PTSD. The brain areas involved include the hippocampus, medial prefrontal cortex and amygdala, that are central to the neural circuitry of traumatic stress. Most functional neuroimaging studies to date have focused on specific cognitive tasks to examine brain functioning in various psychiatric disorders.