Meeting Banner
Abstract #0522

Ultra-Fast fMRI Reveals High-Frequency Fluctuations in Response to Neuronal Discharges

Pierre LeVan1, Julia Jacobs2, Vasumathi Jayakumar1, Jrgen Hennig1

1Radiology, Medical Physics, University Medical Center Freiburg, Freiburg, Baden-Wrttemberg, Germany; 2Neuropediatrics and Muscular Diseases, University Medical Center Freiburg, Freiburg, Baden-Wrttemberg, Germany

FMRI hemodynamics are generally assumed to be prolonged and slow-varying at timescales of several seconds and can thus be adequately sampled at conventional fMRI temporal resolutions of 2-3 seconds. In contrast, the current study investigates high-frequency (>0.5Hz) fMRI fluctuations measured by the whole-brain ultra-fast MR-encephalography (MREG) sequence (100ms temporal resolution), following epileptic discharges recorded by EEG. In 67% of the analyzed spike types, a cluster of voxels showing significant high-frequency fluctuations following the spikes could be identified in brain regions concordant with the spike field. MREG opens up new avenues for the localization of neuronal activity with high spatiotemporal resolution.

Abstract PDF Presentation Video

Keywords

accurate activation activity additionally advanced agreement among applicable artifacts audience avenues baden bold brain canonical cardiac central channel classified clinical cluster clusters compatible computing concentric concordance concordant considerable consumption corrected cortex council courses coverage cutoff degree detect development directly discharges diseases distinct elucidated elusive envelope epilepsy epileptic example examples expert fast faster field filtering fluctuations focal formed frequency frequent frontal functional gradient grant highly hugger human identification identified impact initial insufficient investigates investigation isotropic localization locked looking maps marked matrix mechanisms medical minute mixed morphology motion muscular neurologist neuronal noise opens origin oxygen pass patients permutation physics power preprocessed processing profiles pulse radiology recordings reflect regressing related remain remaining remove removing reported representative resolution respiratory response responses resting reveals sample scales shells shortly shot simultaneous slow spatial spike spikes statistical supported system target temporal topographies trajectories transform trio twelve types ultra underwent unlikely usually white whole window