One of the mantras all of us inherited from our first lessons in neuroanatomy is that in the brain connectivity determines function. However, when we first looked at the beautiful images of a motor cortex activating when we move our fingers, we got the feeling we could bypass the analysis of brain connectivity to grasp the relation between brain activity and behaviour.
In recent years, the steady development of MRI techniques for visualising and quantifying anatomical and functional brain connectivity (although indirectly and with large approximations) changed our perspectives. Interestingly, reliable information about brain connectivity was derived from MRI signal that was earlier considered to be uninteresting noise. Most importantly, by investigating the patterns of covariation of brain connectivity across different regions, we became able to gain information about the functional organization of the brain and to approximate inter-regional differences in its microstructure.
In this talk I will describe how the study of these structures of connectivity evolved in the last years, the results it yielded in terms of brain functions, and what can we expect from it in the near future.