Fear

Fear is an alerting signal in response to a known, identifiable source of threat. Fear is different from anxiety: Anxiety is more of a diffuse and vague [Page 861]sense of apprehension without a clear focus. In other words, the source of threat is known in fear, and it is usually unclear in anxiety. These two mechanisms, which are closely overlapping in symptomatology and underlying brain mechanisms, serve a vital purpose in protection of the organism against threats of different levels. Although in the modern era most enjoy a safer life, humans until a few centuries ago needed a higher level of threat awareness to survive. In that past context, a sensitive alarm system that could bring the brain and body to a level of preparedness ...