Brain Anomaly Leaves Woman Without Fear: "- Sent using Google Toolbar"
Fear, like pain, is a protective mechanism meant to ensure your well being. In this rare case a woman was found to be lacking an amygdala, a small almond shaped structure in the brain very involved in fear response, on both sides of the brain. Consequently she finds herself in situations that would normally evoke fear in most people but she has no fear whatsoever. Sometimes this has turned out to serve her well, like the time she threatened her attacker and scared him off. Most would agree that she was very fortunate in this situation though.
The amygdala is part of the larger limbic system which also includes the hypothalamus, dorsal roots, and dorsal horn of the spinal cord.
Chiropractic adjustment of the cervical spine can affect deep brain structures through activation of joint mechanorecptors. Although I don't know of any studies which have been done in this area I think it would be a very good idea to explore.