http://www.nitrc.org/forum/forum.php?forum_id=5358 <table border="0" width="100%"><tr><td align="left"/><td align="right"><a href="http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&amp;cmd=Link&amp;LinkName=pubmed_pubmed&amp;from_uid=26174326">Related Articles</a></td></tr></table> <p><b>Vascular coupling in resting-state fMRI: evidence from multiple modalities.</b></p> <p>J Cereb Blood Flow Metab. 2015 Jul 15;</p> <p>Authors: Zhu DC, Tarumi T, Khan MA, Zhang R</p> <p>Abstract<br/> Resting-state functional magnetic resonance imaging (rs-fMRI) provides a potential to understand intrinsic brain functional connectivity. However, vascular effects in rs-fMRI are still not fully understood. Through multiple modalities, we showed marked vascular signal fluctuations and high-level coupling among arterial pressure, cerebral blood flow (CBF) velocity and brain tissue oxygenation at &lt;0.08 Hz. These similar spectral power distributions were also observed in blood oxygen level-dependent (BOLD) signals obtained from six representative regions of interest (ROIs). After applying brain global, white-matter, cerebrospinal fluid (CSF) mean signal regressions and low-pass filtering (&lt;0.08 Hz), the spectral power of BOLD signal was reduced by 55.6% to 64.9% in all ROIs (P=0.011 to 0.001). The coherence of BOLD signal fluctuations between an ROI pair within a same brain network was reduced by 9.9% to 20.0% (P=0.004 to &lt;0.001), but a larger reduction of 22.5% to 37.3% (P=0.032 to &lt;0.001) for one not in a same network. Global signal regression overall had the largest impact in reducing spectral power (by 52.2% to 61.7%) and coherence, relative to the other three preprocessing steps. Collectively, these findings raise a critical question of whether a large portion of rs-fMRI signals can be attributed to the vascular effects produced from upstream changes in cerebral hemodynamics.Journal of Cerebral Blood Flow &amp; Metabolism advance online publication, 15 July 2015; doi:10.1038/jcbfm.2015.166.<br/> </p><p>PMID: 26174326 [PubMed - as supplied by publisher]</p> en-us Copyright 2000-2026 NITRC OSI Sun, 03 May 2026 2:29:40 GMT http://blogs.law.harvard.edu/tech/rss NITRC RSS generator