Autonomic Function in the Neonate: III. Methodological Considerations

r OR SOME TIME, we have been inter-ested in the definition of stable character-istics of the autonomic nervous system of an individual at a given time of life. We have been led in the course of our studies to some fundamental considerations of autonomic activity and the development of the methods of data collection and analy-sis that are to be presented in this report. As a result of this detailed inquiry, we have been able to develop a conceptual scheme appropriate for the study of cardiac re-sponses that has permitted differentiation of individual newborn infants. The indi-vidual, so defined, can be studied over a period of time and significant trends de-tected. Such studies may ultimately contribute to the solution of problems that have stimulated investigators for many years: What is the individual predisposition to so-called psychosomatic disease, to anxiety, and to obvious disorders of autonomic nervous system function? Our concern, broadly, is to learn more of the constitu-tionally determined aspects of visceral and somatic behavior in the individual