Andreas Engel. "Intrinsic and extrinsic coupling modes in (social) cognition"

Dynamic functional coupling constitutes a key feature of brain activity, which exhibits rich spatiotemporal patterning and strongly modulates cognitive processing. Much of this coupling is intrinsically generated, i.e., not imposed by entrainment to an external stimulus or movement but emerging from the connectivity of cortical and subcortical networks. However, interactions with the environment, e.g. in social contexts, can lead to extrinsic coupling reflecting entrainment to stimuli, actions, or temporally structured external events. I will discuss evidence for two distinct types of coupling modes which seem to reflect the operation of different coupling mechanisms. One type arises from phase coupling of band-limited oscillatory signals, whereas the other results from coupled aperiodic fluctuations of signal envelopes. The two coupling modes differ in their dynamics, their origins, their putative functions and possibly also their degree of extrinsic entrainment. I will propose that the concept of coupling modes can provide a framework for capturing the dynamics of neuronal interactions at multiple spatial and temporal scales.