Task-Evoked Negative BOLD Response in the Default Mode Network Does Not Alter Its Functional Connectivity.

TitleTask-Evoked Negative BOLD Response in the Default Mode Network Does Not Alter Its Functional Connectivity.
Publication TypeJournal Article
Year of Publication2018
AuthorsRazlighi QR
JournalFront Comput Neurosci
Volume12
Pagination67
Date Published2018
ISSN1662-5188
Abstract

While functional connectivity networks are often extracted from resting-state fMRI scans, they have been shown to be active during task performance as well. However, the effect of an in-scanner task on functional connectivity networks is not completely understood. While there is evidence that task-evoked positive BOLD response can alter functional connectivity networks, particularly in the primary sensorimotor cortices, the effect of task-evoked negative BOLD response on the functional connectivity of the Default mode network (DMN) is somewhat ambiguous. In this study, we aim to investigate whether task performance, which is associated with negative BOLD response in the DMN regions, alters the time-course of functional connectivity in the same regions obtained by independent component analysis (ICA). ICA has been used to effectively extract functional connectivity networks during task performance and resting-state. We first demonstrate that performing a simple visual-motor task alters the temporal time-course of the network extracted from the primary visual cortex. Then we show that despite detecting a robust task-evoked negative BOLD response in the DMN regions, a simple visual-motor task does not alter the functional connectivity of the DMN regions. Our findings suggest that different mechanisms may underlie the relationship between task-related activation/deactivation networks and the overlapping functional connectivity networks in the human large-scale brain networks.

DOI10.3389/fncom.2018.00067
Alternate JournalFront Comput Neurosci
PubMed ID30177878
PubMed Central IDPMC6109759
Grant ListK01 AG044467 / AG / NIA NIH HHS / United States