John A. Sexton1,2, James Chris Gatenby1,3, John C. Gore1,3
1Vanderbilt University Institute of Imaging Science, Nashville, TN, USA; 2Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; 3Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA
We investigate the effects of changing SENSE acceleration factor R on the relative contributions of physiological noise to the total noise of an fMRI time series, fMRI sensitivity, and temporal signal stability at 7T. We observe decreases in the contributions of physiological noise as R increases, and we find excellent agreement between measured TSNR data and a theoretical model. We conclude that acquiring data with R = 4 is appropriate for single-shot EPI fMRI experiments like ours at 7T, and that parallel imaging coils with many elements can significantly improve fMRI results at high field.