TY - JOUR
T1 - Ultra-high field parallel imaging of the superior parietal lobule during mental maze solving
AU - Jerde, Trenton A.
AU - Lewis, Scott M.
AU - Goerke, Ute
AU - Gourtzelidis, Pavlos
AU - Tzagarakis, Haris
AU - Lynch, Joshua
AU - Moeller, Steen
AU - Van de Moortele, Pierre-Francois
AU - Adriany, Gregor
AU - Trangle, Jeran
AU - Ugurbil, Kamil
AU - Georgopoulos, Apostolos P
PY - 2008/6/1
Y1 - 2008/6/1
N2 - We used ultra-high field (7 T) fMRI and parallel imaging to scan the superior parietal lobule (SPL) of human subjects as they mentally traversed a maze path in one of four directions (up, down, left, right). A counterbalanced design for maze presentation and a quasi-isotropic voxel (1.46 × 1.46 × 2 mm thick) collection were implemented. Fifty-one percent of single voxels in the SPL were tuned to the direction of the maze path. Tuned voxels were distributed throughout the SPL, bilaterally. A nearest neighbor analysis revealed a "honeycomb" arrangement such that voxels tuned to a particular direction tended to occur in clusters. Three-dimensional (3D) directional clusters were identified in SPL as oriented centroids traversing the cortical depth. There were 13 same-direction clusters per hemisphere containing 22 voxels per cluster, on the average; the mean nearest-neighbor, same-direction intercluster distance was 9.4 mm. These results provide a much finer detail of the directional tuning in SPL, as compared to those obtained previously at 4 T (Gourtzelidis et al. Exp Brain Res 165:273-282, 2005). The more accurate estimates of quantitative clustering parameters in 3D brain space in this study were made possible by the higher signal-to-noise and contrast-to-noise ratios afforded by the higher magnetic field of 7 T as well as the quasi-isotropic design of voxel data collection.
AB - We used ultra-high field (7 T) fMRI and parallel imaging to scan the superior parietal lobule (SPL) of human subjects as they mentally traversed a maze path in one of four directions (up, down, left, right). A counterbalanced design for maze presentation and a quasi-isotropic voxel (1.46 × 1.46 × 2 mm thick) collection were implemented. Fifty-one percent of single voxels in the SPL were tuned to the direction of the maze path. Tuned voxels were distributed throughout the SPL, bilaterally. A nearest neighbor analysis revealed a "honeycomb" arrangement such that voxels tuned to a particular direction tended to occur in clusters. Three-dimensional (3D) directional clusters were identified in SPL as oriented centroids traversing the cortical depth. There were 13 same-direction clusters per hemisphere containing 22 voxels per cluster, on the average; the mean nearest-neighbor, same-direction intercluster distance was 9.4 mm. These results provide a much finer detail of the directional tuning in SPL, as compared to those obtained previously at 4 T (Gourtzelidis et al. Exp Brain Res 165:273-282, 2005). The more accurate estimates of quantitative clustering parameters in 3D brain space in this study were made possible by the higher signal-to-noise and contrast-to-noise ratios afforded by the higher magnetic field of 7 T as well as the quasi-isotropic design of voxel data collection.
KW - Directional tuning
KW - Parallel imaging
KW - Spatial cognition
KW - Superior parietal lobule
KW - Ultra-high field fMRI
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U2 - 10.1007/s00221-008-1318-8
DO - 10.1007/s00221-008-1318-8
M3 - Article
C2 - 18305932
AN - SCOPUS:44349181365
VL - 187
SP - 551
EP - 561
JO - Experimental Brain Research
JF - Experimental Brain Research
SN - 0014-4819
IS - 4
ER -