title: Depth-dependence of visual signals in the human superior colliculus at 9.4 T.
abstract: The superior colliculus (SC) is a layered structure located in the midbrain. We exploited the improved spatial resolution and BOLD signal strength available at 9.4 T to investigate the depth profile of visual BOLD responses in the human SC based on distortion-corrected EPI data with a 1 mm isotropic resolution. We used high resolution (350 µm in-plane) anatomical images to determine regions-of-interest of the SC and applied a semi-automated method to segment it into superficial, intermediate, and deep zones. A greater than linear increase in sensitivity of the functional signal at 9.4 T allowed us to detect a statistically significant depth pattern in a group analysis with a 20 min stimulation paradigm. Descriptive data showed consistent depth profiles also in single individuals. The highest signals were localized to the superficial layers of the right and left SC during contralateral stimulation, which was in good agreement with its functional architecture known from non-human primates. This study thus demonstrates the potential of 9.4 T MRI for functional neuroimaging even in deeply located, particularly challenging brain structures such as the SC. Hum Brain Mapp 38:574-587, 2017. © 2016 Wiley Periodicals, Inc.
authors.affiliation: High-Field MR, Max Planck Institute for Biological Cybernetics, Tuebingen, DE, Germany.|Biomedical Magnetic Resonance, University Hospital Tuebingen, Tuebingen, DE, Germany.|Graduate School of Neural and Behavioural Sciences/International Max Planck Research School, University of Tuebingen, Tuebingen, DE, Germany.|Division of Neuropsychology, Centre for Neurology, Hertie-Institute for Clinical Brain Research, Tuebingen, DE, Germany.
authors.forename: Joana R
authors.initials: JR
authors.lastname: Loureiro
authors.affiliation: High-Field MR, Max Planck Institute for Biological Cybernetics, Tuebingen, DE, Germany.|Biomedical Magnetic Resonance, University Hospital Tuebingen, Tuebingen, DE, Germany.
authors.forename: Gisela E
authors.initials: GE
authors.lastname: Hagberg
authors.affiliation: Biomedical Magnetic Resonance, University Hospital Tuebingen, Tuebingen, DE, Germany.|Department of Psychiatry and Psychotherapy, University of Tuebingen, Tuebingen, DE, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Ethofer
authors.affiliation: Biomedical Magnetic Resonance, University Hospital Tuebingen, Tuebingen, DE, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Erb
authors.affiliation: High-Field MR, Max Planck Institute for Biological Cybernetics, Tuebingen, DE, Germany.
authors.forename: Jonas
authors.initials: J
authors.lastname: Bause
authors.affiliation: High-Field MR, Max Planck Institute for Biological Cybernetics, Tuebingen, DE, Germany.|Biomedical Magnetic Resonance, University Hospital Tuebingen, Tuebingen, DE, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Ehses
authors.affiliation: High-Field MR, Max Planck Institute for Biological Cybernetics, Tuebingen, DE, Germany.|Biomedical Magnetic Resonance, University Hospital Tuebingen, Tuebingen, DE, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Scheffler
authors.affiliation: Graduate School of Neural and Behavioural Sciences/International Max Planck Research School, University of Tuebingen, Tuebingen, DE, Germany.|Division of Neuropsychology, Centre for Neurology, Hertie-Institute for Clinical Brain Research, Tuebingen, DE, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Himmelbach
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D003867:Depth Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology; D017603:Signal Detection, Psychological / Q000502:physiology; D013477:Superior Colliculi / Q000000981:diagnostic imaging* / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: SC; depth analysis; high resolution