Considering the voluminous literature concerned with the anatomy and physiology of what one might call the visceral central nervous system in contradistinction to those regions of the central nervous system dealing with somatic functions, one is surprised how few are the really well established facts. It seems as if in the visceral sphere we still were in the "center" period. In the somatic sphere we have passed such a period and have learned how much more complicated matters are and how single nervous functions must always be studied as a part of the whole and not as in an imaginative isolation but shaped by the functional state of the whole organ.
Even terms almost sacred, such as "respiratory center," begin to make one feel somewhat uncomfortable. Circumstances appear still more doubtful with regard to the other so-called visceral centers in the medulla oblongata. Eighty years ago, Claude Bernard1 punctured
HILLER F, TANNENBAUM A. THE NERVOUS REGULATION OF SUGAR METABOLISMI. EXPERIMENTAL STUDIES. Arch NeurPsych. 1929;22(5):901-918. doi:10.1001/archneurpsyc.1929.02220050039003