Cortical surface-based analysis - I. Segmentation and surface reconstruction

Several properties of the cerebral cortex, including its columnar and lamin ar organization, as well as the topographic organization of cortical areas, can only be properly understood in the context of the intrinsic two-dimens ional structure of the cortical surface. In order to study such cortical pr operties in humans, it is necessary to obtain an accurate and explicit repr esentation of the cortical surface in individual subjects. Here we describe a set of automated procedures for obtaining accurate reconstructions of th e cortical surface, which have been applied to data from more than 100 subj ects, requiring little or no manual intervention. Automated routines for un folding and flattening the cortical surface are described in a companion pa per. These procedures allow for the routine use of cortical surface-based a nalysis and visualization methods in functional brain imaging. (C) 1999 Aca demic Press.