The shorter wave rhythms of the spectrum, however, (illustration 1, underneath the day rhythm) are purely endogenous autonomic functional variations which have no immediate link to the rhythms of the environment. Instead, a special organizational principle shows itself in this area (illustration 6): So you find the highest frequency rhythmic processes in the area of the nervous system. They serve here to change information, i.e. for the absorption, transportation and processing of information which is encoded into rhythmic signals.
The slow rhythms of the autonomic area, however, primarily serve the metabolism and its functional areas. They regulate the intake and ex­cre­tion of sub­stances, di­ges­tion, se­cre­tion and en­ergy stor­age.

While the in­for­ma­tional rhythms are strictly bound to highly dif­fer­en­ti­ated spa­tial struc­tures of the nerv­ous sys­tem, the meta­bolic rhythms more or less con­cern all tis­sue and are spa­tially much less speci­fied. The sys­tem of the rhyth­mic func­tions of trans­por­ta­tion and dis­tri­bu­tion is the tran­si­tion be­tween these two com­pletely dif­fer­ent func­tional ar­eas, es­pe­cially with the rhythms of circulation and breathing.