High-resolution intersubject averaging and a coordinate system for the cortical surface

Abstract

Abstract:The neurons of the human cerebral cortex are arranged in a highly folded sheet, with the majority of the cortical surface area buried in folds. Cortical maps are typically arranged with a topography oriented parallel to the cortical surface. Despite this unambiguous sheetlike geometry, the most commonly used coordinate systems for localizing cortical features are based on 3-D stereotaxic coordinates rather than on position relative to the 2-D cortical sheet. In order to address the need for a more natural surface-based coordinate system for the cortex, we have developed a means for generating an average folding pattern across a large number of individual subjects as a function on the unit sphere and of nonrigidly aligning each individual with the average. This establishes a spherical surface-based coordinate system that is adapted to the folding pattern of each individual subject, allowing for much higher localization accuracy of structural and functional features of the human brain. Hum. Brain Mapping 8:272-284, 1999. 1999 Wiley-Liss, Inc.

Cortical folding of the preterm brain: a longitudinal analysis of extremely preterm born neonates using spectral matching

“…2005), or on inflating surfaces to a common template which is usually a sphere, such as FreeSurfer (Fischl et al. 1999) and Spherical Demons (Yeo et al. 2010).…”

The impact of correction on MP2RAGE cortical T1 and apparent cortical thickness at 7T

“…In addition, for each vertex and (white and pial) surface, the change in the vertex's location (in mm, along the vertex's normal) for the corrected (vs original) volume was computed and projected onto the surface (Fujimoto et al, 2014). All surface maps were coregistered to the “fsaverage” subject using sphere‐based alignment (Fischl, Sereno, Tootell, & Dale, 1999) for further (statistical) analyses. Final surface maps were visualized using the Connectome Workbench v1.2.3 viewer (Washington University School of Medicine, Saint Louis, MO, USA) after conversion of the inflated surfaces and overlays to a compatible format.…”

Tonotopic maps in human auditory cortex using arterial spin labeling

“…This 3D cortical representation was used for group alignment purposes to the aim of both computation and visualization (after inflation) of group maps. The group cortical surfaces were produced taking into account the individual subject's cortical curvature via the “moving target group averaging approach” of the cortex‐based alignment (CBA) procedure (Fischl et al, 1999; Goebel et al, 2006). Anatomical masks of the temporal lobe and the primary auditory cortex were manually drawn in the common CBA space based on (Baumann et al, 2013; Bonte et al, 2013; Kim et al, 2000; see Fig.…”