http://www.nitrc.org/forum/forum.php?forum_id=4965 <table border="0" width="100%"><tr><td align="left"/></tr></table> <p><b>fMRI Contrast at High and Ultrahigh Magnetic Fields: Insight from Complementary Methods.</b></p> <p>Neuroimage. 2015 Mar 17;</p> <p>Authors: Ciobanu L, Solomon E, Pyatigorskaya N, Roussel T, Le Bihan D, Frydman L</p> <p>Abstract<br/> This manuscript examines the origins and nature of the function-derived activation detected by magnetic resonance imaging at ultrahigh fields using different encoding methods. A series of preclinical high field (7T) and ultra-high field (17.2T) fMRI experiments were performed using gradient echo EPI, spin echo EPI and spatio-temporally encoded (SPEN) strategies. The dependencies of the fMRI signal change on the strength of the magnetic field and on different acquisition and sequence parameters were investigated. Artifact-free rat brain images with good resolution in all areas, as well as significant localized activation maps upon forepaw stimulation, were obtained in a single scan using fully refocused SPEN sequences devoid of T2* effects. Our results showed that, besides the normal T2-weighted BOLD contribution that arises in spin-echo sequences, fMRI SPEN signals contain a strong component caused by apparent T1-related effects, demonstrating the potential of such technique for exploring functional activation in rodents and on humans at ultrahigh fields.<br/> </p><p>PMID: 25795340 [PubMed - as supplied by publisher]</p> en-us Copyright 2000-2026 NITRC OSI Sat, 02 May 2026 1:37:39 GMT http://blogs.law.harvard.edu/tech/rss NITRC RSS generator