Biomedical signals constitute the "epiphany", i.e the external manifestation of the functioning of the involved physiological systems. Many of these systems like cardiovascular or central nervous systems are indeed complex and that is confirmed by both the structure of physiological modelling which is generally employed to explain various pathophysiological phenomena and by the richness of information detectable from the signals, in most of the times with strong linear and nonlinear interactions with other biological systems. In particular, this behaviour may be accordingly described by means of what was called MMMM-paradigm (i.e. multivariate, multiorgan, multimodal and multiscale). Such an approach to physiological studies emphasizes where the genesis of their complexity is potentially allocated and how it is possible to detect information from it, through a proper processing of the available data. It is believed that this paradigm will contribute to a more olistic vision of pathophysiology, by considering patient as a whole not simply as the sum of his/her constituent parts. Medical diagnosis a well as a modern concept of preventive medicine which has to take care also of healthy population could largely profit by this methodological and technological approach.