Padmavathi Sundaram1,2, Robert V. Mulkern1,
William M. Wells2, Christina Triantafyllou3, Tobias
Loddenkemper4, Ellen J. Bubrick5, Darren B. Orbach1,2
1Radiology, Children's
Hospital Boston, Harvard Medical School, Boston, MA, United States; 2Radiology,
Brigham & Women's Hospital, Harvard Medical School, Boston, MA, United
States; 3Brain & Cognitive Sciences, Massachusetts Institute
of Technology, Cambridge, MA, United States; 4Neurology,
Children's Hospital Boston, Harvard Medical School, Boston, MA, United
States; 5Neurology, Brigham & Women's Hospital, Harvard
Medical School, Boston, MA, United States
We recently developed a functional neuroimaging technique called encephalographic MRI. Our method acquires concurrent scalp electroencephalography and rapid gradient echo EPI. We imaged fast (20-200 ms), high amplitude (> 50 uV) cortical discharges in a cohort of focal epilepsy patients. We found easily detectable MR magnitude and phase changes concurrent with the interictal spike with a lag of milliseconds. Due to the time scale of the responses, localized changes in blood flow are unlikely to cause the MR signal changes. While the precise underlying mechanisms are unclear, in this study we empirically investigate one potentially important confound motion.