Low Frequency BOLD Fluctuations and Brain Functional Connectivity
نویسنده
چکیده
Functional connectivity refers to correlations between spatially remote neurophysiological events as described by Friston & Büchel. Functional connectivity is simply a statement about the observed correlations and does not imply how the correlation is mediated. Effective connectivity is closer to inter-neuronal connectivity as it refers to influence that one neuronal system exerts over another (Friston & Büchel). The difference between functional and effective connectivity is related to differences in the time and scale of the measurements; e.g. hemodynamics response function vs. spike trains. The following text focuses on the relationship between functional connectivity and low frequency fluctuations detected in resting state brain activity with BOLD fMRI.
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