Abstract
No field of biologic science is at present attracting closer attention than the autonomic nervous system. Its problems are being assailed from all angles, morphologic, physiologic, chemical and clinical, and each line of attack is yielding new knowledge. Peripherally, the intricate pattern of neurons is becoming linked with humoral physiology; centrally, higher mechanisms for control are being discovered which appear to coordinate the autonomic and somatic functions into a still more harmonious whole. Bichat's original concept of the complete independence of the "organic" nervous system is being abandoned, and the significance of Bernard's broad conception of the milieu intérieur has at last come into its own. New ideas springing up in the full tide of present-day knowledge leave behind a feeling of instability and uncertainty, and yet despite many doubts certain fundamental concepts have emerged from the mass of evidence gathered in the past. The growth of such ideas is