1Department of physics, CNR ISC UOS Roma Sapienza, Rome, Italy, 2Department of anatomical, histological, forensic and of the locomotor system science, Morphogenesis & Tissue Homeostasis, Sapienza University, Rome, Italy, 3MIRCen, CEA/DSV/I2BM, Fontenay-Aux Roses, France, 4Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy