Peter A. Levine, PhD: The Healing Trauma Online Course - Part 1... Trauma happens when our body prepares to protect us but we are overwhelmed. What we were doing to protect ourselves generates the symptoms of trauma (preparing to fight or flight). Trauma occurs when we are threatened or we perceive we are threatened. Our body goes into a protective reaction when we are getting ready to fight or flight and our body gets stuck, and our body keeps telling our mind that there is still a threat.
Great description of how ACES (adverse childhood experiences) and subsequent stress affect the child's brain development . manifesting themselves in adulthood in health issues ranging from increased stress to substance abuse.