A Cortical and Cerebellar Parcellation System for Speech Studies

A neuroanatomical parcellation system is described which encompasses the entire cerebral cortex and the cerebellum. The cortical system is a modified version of the scheme described by Caviness et a!. (1996) and is designed particularly for studies of speech processing. The cerebellum is parcellated into 6 cortical regions of interest (ROis) and an ROI representing the deep cerebellar nuclei in each hemisphere. The boundaries of each ROI are based on individual anatomical markers that are clearly visible from standard structural MRI acquisitions. The system petmits averaging of functional imaging data sets fi·om multiple subjects while accounting for individual anatomical variability. Used in conjunction with region-of-interest analysis techniques such as that described by Nieto-Castanon et a!. (2003), the parcellation system provides a more powerful means of analyzing functional data.