HUMAN CINGULATE AND PARACINGULATE SULCI - PATTERN, VARIABILITY, ASYMMETRY, AND PROBABILISTIC MAP

Recent advances in functional neuroimaging of the human cerebral corte x revived interest in the study of the cortical morphology at bath mac ro- and microscopic levels. By means of high-resolution magnetic reson ance imaging (MRI), in vivo images of the human brain can be acquired and used to aid localization of the functional maps. The goal of the p resent study was to determine variability in the occurrence and locati on of the cingulate sulcus (GS) and the paracingulate sulcus (PCS). Br ain MRIs of 247 healthy young volunteers were obtained and transformed into a standardized stereotaxic Space (Talairach and Tournoux, 1988). The CS and PCS were marked in 494 hemispheres using software capable of real-time movement through a 3-D volume. The markers were used to g enerate a probabilistic map of the CS and PCS. The individual MRI imag es were also evaluated for the presence and location df the following morphological features: the continuity of the CS, the presence of vert ically oriented branches of the CS, the presence of the PCS, and the p resence of the intralimbic sulcus. Tbe results revealed considerable v ariability in the location of some of the above morphological features and a striking hemispheric asymmetry in the prominence of the PCS. Th e results of four previous blood-flow activation studies of speech con trol were used to illustrate the relevance bf our morphological findin gs for functional neuroimaging of the human anterior cingulate cortex.