Imaging connectivity: MRI and the structural networks of the brain.

Magnetic resonance imaging (MRI) is a flexible and widely available neuroimaging technique. Structural MRI and diffusion MRI, in particular, provide information about connectivity between brain regions which may be combined to obtain a picture of entire neural networks, or the so-called connectome. In this review we outline the principles of MR-based connectivity analysis, discuss what relevant information it can provide for clinical and non-clinical neuroscience research, and outline some of the outstanding needs which future work will aim to meet.