2010 Volume 12 Issue 3+4 Pages 133-139
The past decade has seen several lines of research converge on the idea that phase-amplitude cross-frequency coupling (CFC) may play an important functional role in local computation and long-range communication in large-scale brain networks. The discovery that strong CFC exists in multiple brain areas including the neocortex, hippocampus, and basal ganglia suggests that CFC reflects functional activation of these areas. The finding that the exact frequencies coupled together vary as a function of area and task imply that independent channels of coupling may coexist simultaneously during task performance. The dynamic regulation of coupling strength indicates that CFC has the necessary temporal resolution required for the effective modulation of distinct functional networks. Finally, the discovery that hippocampal CFC strength is correlated with learning task performance suggests that phase-amplitude CFC may help regulate the network of synaptic connections vital for memory and learning. Together, these findings suggest a framework where phase-amplitude CFC parses neuronal computation into discrete chunks of activity that are ideal for attention, learning, and memory, and that these multi-scale building blocks are entrained to both rhythmic, external sensory and motor activity as well as the internal fronto-limbic activity associated with motivation, decision making, and memory.
