Fear, according to the DSM-5, is the emotional response to real or perceived imminent threat, whereas anxiety is anticipation of future threat (APA, 2013). All anxiety disorders contain some degree of fear or anxiety symptoms (often in combination with avoidant behaviors), although their causes and severity differ. Trauma-related disorders may also, but not necessarily, contain fear and anxiety symptoms, but their primary distinguishing criterion is exposure to a traumatic event. Trauma can occur at any point in life. It might not surprise you to discover that traumatic events are likely to have a greater effect on children than on adults. Early-life traumatic experiences, such as childhood sexual abuse, may influence the physiology of the developing brain. Later in life, there is a chronic hyperarousal of the stress response, making the individual vulnerable to further stress and stress-related disease.