SUMMARY Among imaging technologies available fMRI is a powerful modality that allows non invasive evaluation of brain function with high spatial and temporal resolution. It is based on changes in the MRI signal, detected by echo planar sequence, due to fluctuation of ratio of deoxygenated relative to oxygenated blood. Signal changes have to be isolated from noise from different sources, making processing time consuming. Mathematic and statistical analysis has to be done by a multidisciplinary team. fMRI results can have different clinical application and generate valuable knowledge.