How can neuroimaging inform us about the function of brain structures? This simple question immediately brings out two pertinent issues: (i) an inference problem, namely the fact that the function of a region can only be asserted after observing a large array of experimental conditions or contrasts; and (ii) the fact that the identity of a region can only be defined with accuracy at the individual level, because of intrinsic differences between subjects. To overcome this double challenge, we consider an approach based on the deep phenotyping of behavioral responses from task data acquired using functional Magnetic Resonance Imaging. The concept of functional fingerprint-which subsumes the accumulation of functional information at a given brain location-is herein discussed in detail through concrete examples taken from the Individual Brain Charting dataset.