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Nuclear Magnetic Resonance (NMR) includes a set of non-invasive techniques, which can be sensitized to many phenomena of biomedical interest. These include blood perfusion, metabolic and molecular dynamics, water diffusion, and many others. These properties allowed the establishment of MR Imaging and Spectroscopy as important techniques for the study of the brain function and structure and of the relevant diseases. Furthermore, MR development resulted in a large everyday-life impact, including advanced diagnostic tools.
Beyond its capability to produce excellent tomographic imaging of the central nervous system, NMR can be exploited quantitatively, given that the sample magnetization can be manipulated in order to obtain a signal capable of mapping one or several physical or chemical parameters of the sample itself.
Activity of our Laboratory are focused on several topics that can be gathered together in two major topics. First, the development of MR techniques and of the relevant processing methods, mainly in the fields of spectroscopy and quantitative imaging. Second, the use of these tailored techniques in some fields of great interest for the applied sciences, related to the physiology and pathology of human brain function. These embrace the brain metabolic dynamics and the changes of brain functional networks induced by physiologic activity or pathology.Magnetic Resonance Imaging (MRI) has rapidly become one of the most important and fruitful tool in both neuroscience research and clinical practice.
The functional approach, specifically functional Magnetic Resonance Imaging (fMRI), is the most generally used technique for the investigation of human cognition. fMRI is able to map activated brain regions by taking advantage of the local relation between physiological function, energy metabolism and blood supply. In fact, the Blood Oxygenation Level Dependent (BOLD) signal, on which fMRI is based, reflects a complex relationship between changes in local blood volume (CBV) blood flow (CBF) and oxygen metabolism (CMRO2), as a consequence of neuronal activity.
BOLD contrast derives from magnetic field inhomogeneities induced by deoxyhemoglobine concentration in red blood cells in blood vessels with respect to surrounding space. Immediately after neuronal activation, a decrease of BOLD signal would be expected, due to the increase of oxygen consumption. Actually, an increase of BOLD signal is found, due to the increase in cerebral blood flow determining an oversupply of oxygen in working areas. fMRI sequences are designed to be sensitive to this gradient of susceptibility generating BOLD signal alteration, which has been suggested to reflect the intra-cortical information processing of a given brain area.

The principal advantages of fMRI are its non-invasive nature, the high spatio-temporal resolution, and the ability in investigating the entire network of brain areas engaged during a tasks. To date fMRI is surely one of the most exciting and promising technique for the in vivo study of brain function and dysfunction, and it is able to optimize clinical processes providing essential information for diagnosis and therapeutic monitoring.