Book excerpt: The third edition of this classic text, extensively revised, is now available in paperback, priced so that all interested physicians can have their own copy. The autonomic nervous system regulates, without conscious awareness, the function of the heart and all other bodily organs. Autonomic failure can cause a variety of seemingly strange symptoms, which may present to general physicians or a wide spectrum of specialists. This book shows how these symptoms can be studied scientifically in order to reach a precise diagnosis and instigate rational treatment.