Introduction

Jansen and Brodal began their treatise on the cerebellum by pointing out its great morphological diversity across species, which appeared striking even within the mammals (Jansen and Brodal, 1954). While intriguing the early anatomists, this fascinating anatomy presents considerable challenges to current methods for imaging, mapping, and measuring morphology. These tasks are further complicated by today's focus on functional imaging, which requires that the brain be mapped in vivo. The cerebellum's gross features and major landmarks are easily distinguished with non-invasive techniques such as conventional magnetic resonance imaging (MRI), but novel techniques are required to discern its individual folia and deep nuclei. While the creation of stereotaxic atlas systems for the cerebral hemispheres has greatly facilitated the exchange and comparison of structural and functional data, the most ubiquitous stereotaxic systems and atlas spaces fail to define the cerebellum sufficiently in terms of its placement or delineation. This chapter describes progress in each of these problem areas. Specifically, it describes the use of a high-resolution cryosectioning approach that produces full-color, three-dimensional image volumes of in-situ anatomy and a multi-scan MRI approach to achieve superior in-vivo image volumes of cerebellar anatomy. It also describes efforts to rectify the standard cerebral atlases with multisubject mappings of this structure by use of informatics techniques and a deformable brain atlas.