Spontaneous brain activity in the default mode network is sensitive to different resting-state conditions with limited cognitive load. Export

@article{citeulike:4743386, abstract = {BACKGROUND: Recent functional MRI (fMRI) studies have demonstrated that there is an intrinsically organized default mode network (DMN) in the resting brain, primarily made up of the posterior cingulate cortex (PCC) and the medial prefrontal cortex (MPFC). Several previous studies have found that the DMN is minimally disturbed during different resting-state conditions with limited cognitive demand. However, this conclusion was drawn from the visual inspection of the functional connectivity patterns within the DMN and no statistical comparison was performed. METHODOLOGY/PRINCIPAL FINDINGS: Four resting-state fMRI sessions were acquired: 1) eyes-closed (EC) (used to generate the DMN mask); 2) EC; 3) eyes-open with no fixation (EO); and 4) eyes-open with a fixation (EO-F). The 2-4 sessions were counterbalanced across participants (n = 20, 10 males). We examined the statistical differences in both functional connectivity and regional amplitude of low frequency fluctuation (ALFF) within the DMN among the 2-4 resting-state conditions (i.e., EC, EO, and EO-F). Although the connectivity patterns of the DMN were visually similar across these three different conditions, we observed significantly higher functional connectivity and ALFF in both the EO and the EO-F conditions as compared to the EC condition. In addition, the first and second resting EC conditions showed significant differences within the DMN, suggesting an order effect on the DMN activity. CONCLUSIONS/SIGNIFICANCE: Our findings of the higher DMN connectivity and regional spontaneous activities in the resting state with the eyes open suggest that the participants might have more non-specific or non-goal-directed visual information gathering and evaluation, and mind wandering or daydreaming during the resting state with the eyes open as compared to that with the eyes closed, thus providing insights into the understanding of unconstrained mental activity within the DMN. Our results also suggest that it should be cautious when choosing the type of a resting condition and designating the order of the resting condition in multiple scanning sessions in experimental design.}, author = {Yan, Chaogan and Liu, Dongqiang and He, Yong and Zou, Qihong and Zhu, Chaozhe and Zuo, Xinian and Long, Xiangyu and Zang, Yufeng}, citeulike-article-id = {4743386}, citeulike-linkout-0 = {http://dx.doi.org/10.1371/journal.pone.0005743}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/19492040}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=19492040}, doi = {10.1371/journal.pone.0005743}, issn = {1932-6203}, journal = {PloS one}, keywords = {default-mode, fmri, functional-connectivity, resting-state}, month = {May}, number = {5}, pages = {e5743+}, posted-at = {2009-06-07 11:56:34}, priority = {2}, publisher = {Public Library of Science}, title = {Spontaneous brain activity in the default mode network is sensitive to different resting-state conditions with limited cognitive load.}, url = {http://dx.doi.org/10.1371/journal.pone.0005743}, volume = {4}, year = {2009} }

TY - JOUR ID - citeulike:4743386 L3 - citeulike-article-id:4743386 N2 - BACKGROUND: Recent functional MRI (fMRI) studies have demonstrated that there is an intrinsically organized default mode network (DMN) in the resting brain, primarily made up of the posterior cingulate cortex (PCC) and the medial prefrontal cortex (MPFC). Several previous studies have found that the DMN is minimally disturbed during different resting-state conditions with limited cognitive demand. However, this conclusion was drawn from the visual inspection of the functional connectivity patterns within the DMN and no statistical comparison was performed. METHODOLOGY/PRINCIPAL FINDINGS: Four resting-state fMRI sessions were acquired: 1) eyes-closed (EC) (used to generate the DMN mask); 2) EC; 3) eyes-open with no fixation (EO); and 4) eyes-open with a fixation (EO-F). The 2-4 sessions were counterbalanced across participants (n = 20, 10 males). We examined the statistical differences in both functional connectivity and regional amplitude of low frequency fluctuation (ALFF) within the DMN among the 2-4 resting-state conditions (i.e., EC, EO, and EO-F). Although the connectivity patterns of the DMN were visually similar across these three different conditions, we observed significantly higher functional connectivity and ALFF in both the EO and the EO-F conditions as compared to the EC condition. In addition, the first and second resting EC conditions showed significant differences within the DMN, suggesting an order effect on the DMN activity. CONCLUSIONS/SIGNIFICANCE: Our findings of the higher DMN connectivity and regional spontaneous activities in the resting state with the eyes open suggest that the participants might have more non-specific or non-goal-directed visual information gathering and evaluation, and mind wandering or daydreaming during the resting state with the eyes open as compared to that with the eyes closed, thus providing insights into the understanding of unconstrained mental activity within the DMN. Our results also suggest that it should be cautious when choosing the type of a resting condition and designating the order of the resting condition in multiple scanning sessions in experimental design. IS - 5 JF - PloS one SN - 1932-6203 TI - Spontaneous brain activity in the default mode network is sensitive to different resting-state conditions with limited cognitive load. PB - Public Library of Science VL - 4 SP - e5743 KW - default-mode KW - fmri KW - functional-connectivity KW - resting-state AU - Yan, Chaogan AU - Liu, Dongqiang AU - He, Yong AU - Zou, Qihong AU - Zhu, Chaozhe AU - Zuo, Xinian AU - Long, Xiangyu AU - Zang, Yufeng PY - 2009/05/29/ UR - http://dx.doi.org/10.1371/journal.pone.0005743 ER -