Meeting Banner
Abstract #2865

High-Resolution Sparse-Sampling FMRI Reveals Tonotopic Organization of Human Inferior Colliculus

David Ress1, Reswanul Khan2, Bharath Chandresekaran3, Seth Koslov3

1Neurobiology, Psychology, Imaging Research Center, Center for Perceptual Systems, The University of Texas at Austin, Austin, TX, United States; 2Neurobiology, Physics, Imaging Research Center, Center for Perceptual Systems, The University of Texas at Austin, Austin, TX, United States; 3Communication Sciences and Disorders, The University of Texas at Austin, Austin, TX, United States

We present a high-resolution sparse-sampling fMRI approach for imaging small auditory brainstem structures. High resolution is obtained with a multi-shot spiral acquisition. Sparse sampling is obtained by two adjustments to the fMRI pulse sequence. First, quiet periods are created by disabling the acquisition gradients for long periods (9 s) to permit delivery of auditory stimuli. Second T1-equilibrium is maintained by continual delivery of slice-selective excitation pulses throughout each scanning run. Using this approach, we have obtained 1.2-mm sampling in human inferior colliculus (IC) with satisfactory contrast-to-noise ratio. The data confirm a laminar organization of stimulus frequency representation in human IC.

Abstract PDF E-Poster Video

Keywords

acquisition activation animal array attention auditory bold boundary central coil compensated complex condition confirm consisted consistent continually contrasts control coordinate create deeper depth discrimination disorders distance dorsal double duration encoding entire evoked facilitate filtered fine five freq frequencies frequency function glover gradients hods human included increasing indicate individual inferior interleaves isometric khan laminar laminated located maintained maps measure motion nature navigated neurobiology noise novel onto organ organization pair parse peak perceptual period periods plication prescription presentation profiles psycho pulses quasi readout received resolution responses runs sampling scanner sciences selective self session sets shot shots silence silent sinusoid slices slightly sound spaced sparse spatial spiral stimuli stimulus structure structures studies subjects substantial superficial superior surface systems task temporal trends typically upon utilized vector ventral versus visual