The human dentate nucleus: a complex shape untangled

• Published in: Neuroscience Vol. 167; no. 4; pp. 965 - 968
• Main Authors: Sultan, F, Hamodeh, S, Baizer, J.S
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 02.06.2010; Elsevier
• Subjects: 3D surface models; Animals; Biological and medical sciences; Brain; Cerebellar Nuclei - anatomy & histology; cerebellum; dentate nucleus; Fundamental and applied biological sciences. Psychology; Humans; Macaca mulatta; Models, Anatomic; motor control; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; Neurology; primates; Vertebrates: nervous system and sense organs; 3D surface models; primates; motor control; cerebellum; dentate nucleus; Cerebellum; Human; Vertebrata; Mammalia; Central nervous system; Primates; Models; Motor control; Dentate nucleus; Encephalon
• ISSN: 0306-4522; 1873-7544
• DOI: 10.1016/j.neuroscience.2010.03.007

Abstract The dentate nucleus is the largest single structure linking the cerebellum to the rest of the brain. The peculiar shape and large size of the human dentate nucleus have sparked a number of theories about the role of the cerebellum in human evolution. Some of the proposed ideas could be explored by comparative studies of humans and apes, but comparative studies are hindered because of the complex three dimensional shape of the human dentate. Here we present a 3D model based on a quantitative reconstruction of the human dentate; this model can facilitate comparative studies. The dentate nucleus has been partitioned into dorsal and ventral lamellae based on sheet thickness. Our data show that the thicker ventral lamella occupies a distinctly smaller portion of the human dentate than previously hypothesized. Within the dorsal lamella there is a medial to lateral increase in depth of dentate folds. However, the dorsal lamella retains a thin sheet thickness unlike the macrogyric ventral lamella, in which sheet thickness is increased. The appearance of larger folds laterally reflects the emergence of secondary folds that could encompass the projection of the cerebellar hemispheres, minimizing convergence of different corticonuclear microzones. Thus, the unique feature of the hominoid dentate is the development of a large surface area and an expansion of its mediolateral width. We propose that this is to allow for a large number of independent corticonuclear modules that can modulate an equal large number of sequential motor acts.