The emergence of a unified cognitive moment relies on the coordination of scattered mosaics of functionally specialized brain regions. Here we review the mechanisms of large-scale integration that counterbalance the distributed anatomical and functional organization of brain activity to enable the emergence of coherent behaviour and cognition. Although the mechanisms involved in large-scale integration are still largely unknown, we argue that the most plausible candidate is the formation of dynamic links mediated by synchrony over multiple frequency bands.

Francisco Varela*, Jean-Philippe Lachaux*, Eugenio Rodriguez, and Jacques Martinerie (2001) "The brainweb: phase synchronization and large-scale integration" in: Nature Rviews Vol 2. (April 2001). p. 229 (online)