Brain is connected! The topology and the metrics of these connections across Central Nervous System (CNS), and Peripheral Nervous System (PNS) reflects a holistic view of human functions, and life. Modern Medicine, in order to properly consider human health, may need to identify new paradigms for diagnostic, and therapeutic approaches. Biological systems are structured and connected in living beings, just as the brain. Indeed, connection between systems, and connection across systems are present. Connections are developed between different elementary units such as neurons, nephrons, cardiomyocyte, etc and between different tissues and organs, generally through a diverse variety of molecules. In this context, the problem is to identify the structures, and the properties of these connections and to identify the mathematical laws describing their dynamic. This approach may potentially answer important medical-related questions through the accurate description of the ways used by Biological Systems to perform the vital functions. Characterization of the networks in and towards the brain may be useful to evaluate diseases alterations in other organs, hence to optimize early diagnostic tools, and treatments. In this paper, some significant applications of brain networks analysis for the assessment of several human pathological mechanisms are reported. Diagnostic imaging based on magnetic resonance may be considered an important field of application for this innovative strategy.