Abstract #1715

Elucidating the Impulse Response Function of SEEP Contrast in the Human Spinal Cord by Means of Event-Related Spin-Echo Spinal FMRI

Chase R. Figley¹, Jordan K. Leitch¹, Celina Nahanni¹, Patrick W. Stroman^1,2

¹Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada; ²Diagnostic Radiology and Physics, Queen's University, Kingston, Ontario, Canada

Event-related fMRI is now a prevalent technique in both systems and cognitive neuroscience, but event-related spinal cord fMRI has not yet been reported. However, with recent methods to reduce motion-related confounds, the sensitivity and specificity of spin-echo spinal fMRI methods have been dramatically improved. Herein, we have capitalized on these improvements to investigate peristimulus signal intensity changes following brief periods of cold thermal stimulation (1 second durations of 22 C) applied to the palm of the hand. The results of this study have refined our understanding of the SEEP (i.e., signal enhancement by extravascular water protons) impulse response function in the human spinal cord, and represent the first successful demonstration of event-related spinal fMRI.