The IRC also operates a 1.5T, whole-body, neuro-optimized GE Signa Horizon LX NV/I MRI system (GE Medical Systems, Waukesha, WI). The 1.5T system has enhanced gradient performance (150 mT/m/ms rise time, 40 mT/m peak) for functional brain imaging. The high gradient strength and rise time provides single image acquisition in under 25 ms using EPI or spiral pulse sequences. Pulse sequences for blood oxygenation level dependent (BOLD) imaging, arterial spin-tagging, diffusion tensor imaging, single-voxel spectroscopy, and all clinical imaging scans are available. The system uses the LX operating system (Version 84M4), an SGI Octane workstation with enhanced reconstruction capabilities (approximately 100 images/sec), and a Sun Ultra (Sun Microsystems, Inc. Mountain View, CA) for real-time interactive control of functional (fMRI) image acquisition, scan parameter selection, image visualization, and image processing. An Advantage Windows Workstation (AWW, GE Medical Systems) can also be used for advanced image processing and analysis of images obtained using fMRI, MR angiography, gated cardiac imaging, velocity encoded phase imaging, and first-pass contrast enhanced imaging.