Jens Schwarzbach: “Functional Connectivity Dynamics”
CiNet 1F Conference Room
Department of Psychiatry and Psychotherapy
University of Regensburg, Germany
Connectivity concerning the human brain is a generic term embracing all possible ways of how connections can emerge in this neural system. Functional connectivity (FC) is the statistical association between time series of physiological signals from different areas, for example in the form of correlations between these time series. The underlying assumption is that brain areas, which exhibit a similar temporal evolution of activity, share information and are connected in a functional manner.
The dominating approach in the literature has been to treat FC as if it were stable over the entire acquisition-period, but that such stationary FC differed between healthy controls and patients afflicted with neuropsychiatric disorders. Fluctuations in connectivity are treated as a mere nuisance, making group comparisons less sensitive and individual assessment of FC unreliable.
Here I argue that changes of functional connectivity are systematic and meaningful and that such functional connectivity dynamics (FCD) gives rise to dynamically regrouping functional networks that underlie complex cognitive abilities. In this view stationary FC would rather constitute a pathological state than describe the functioning of the intact human brain. In my talk I will present a method to reliably estimate the FCD by means of resting-state fMRI on the individual level, opening up the investigation of FCD as a biomarker in Psychiatry and Neurology.