Corticonuclear projection

Jansen and Brodal (1940, 1942) studied the corticonuclear projection of the corpus cerebelli with the Marchi method in cat, rabbit and mactique. They confirmed the uncrossed projection of each hemivermis to the medial nucleus and the vestibular nuclei. In the hemisphere they distinguished an intermediate zone, that projects to Brunner s (1919) interpositus nucleus and a lateral zone, that is connected with the lateral nucleus. They noticed the correspondence between their three-zonal arrangement in the corti-... 

Is the number of modules constant among the mammalian species and are they correlated with the different forms of chemoarchitectonic zonation in the cortex and the white matter These questions only can be answered after a more thorough review of the corticonuclear projection (Sections 6.1.1., 6.1.2., 6.1.4. and 6.1.5.), the chemoarchitectonic evidence on zonation (Section 6.1.3.) and the olivocerebellar and nucleo-cerebellar projections (Section 6.3.) in different mammalian species. The existence of such a basic plan has been questioned (Boegman et al., 1988), not so much because the different maps for parasagittal zonation are mutually exclusive, but mainly because most... 

Corticonuclear projection zones in the cat Correlation with white matter compartments and cytochemical zones... 

Fig. 123. Diagram of the corticonuclear projection in the cat. Based on retrograde labelling of Purkinje cells and their axons after injections of HRP in their target nuclei. A = A zone A = Anterior interposed nucleus ANS = ansiform lobule B = B zone C1-C3 = C1-C3 zones CRII = crus II of the ansiform lobule D1-D2 = D1-D2 zones DV = descendng vestibular nucleus F = fastigial nucleus FLOC = flocculus IP = posterior interposed nucleus L = lateral eerebellar nucleus LOB POST = posterior lobe LOB ANT = anterior lobe LV = Deiters nucleus MVmc = magnocellular medial vestibular nucleus MVpc = parvicellular medial vestibular nucleus PFL = paraflocculus PFLD = dorsal paraflocculus PFLV = ventral paraflocculus PMED = paramedian lobule SV = superior vestibular nucleus I-X = lobules I-X. Bigare (1980).

D and D2 zones in the paraflocculus of the cat is compatible with the anterograde tracing study of Dietrichs (1981b). The corticonuclear projections of the electrophysiol-ogically verified climbing fiber zones b, x, c, Cj, C3 and d[ were determined for lobule... 

Only few observations in primates are available on the corticonuclear projection of the posterior lobe. Haines and Whitworth (1978) and Haines and Patrick (1981) studied the projection of the paramedian lobule and the paraflocculus in the tree shrew Tupaia glis). They concluded that , 3 and a D zone, with a similar topography and corticonuclear projection as in the cat, were present in the paramedian lobule of the tree shrew. The C2 and the D zone continued into the paraflocculus, where the D zone could be subdivided into D, and Dj zones on the basis of its differential projection to the lateral cerebellar nucleus. The organization of the posterior vermis in primates (Haines, 1975a,b) will be dealt with in the Sections on the vestibular cerebellum (6.1.5.) and the olivocerebellar projection (6.3.3.3.). 

Fig. 128. Diagrammatic representation of the corticonuclear projection of lobule V in Galago. There are at least six identifiable corticonuclear projection zones in the lobule V cortex. The vermis consists of zones A and B, the intermediate cortex of three zones C, - C3 and the lateral cortex of a single D zone, f = flocculus IC = intermediate cortex LC = lateral cortex Ivn = lateral vestibular nucleus 1-nia = lateral anterior interposed nucleus m - nia = medial anterior interposed nucleus m - nip = medial posterior interposed nucleus nl = lateral cerebellar nucleus nm = medial nucleus vc = vermal cortex. Haines and Rubertone (1979)...

The corticonuclear projection of the cerebellum of the rat Correlations with zebrin-antigenic compartmentalization... 

The corticovestibular and corticonuclear projections of the flocculus and the caudal vermis. Correlations with cytochemical zones and compartments... 

Although the Zebrin pattern in the caudal vermis is quite distinct and some correlations with the corticonuclear projection zones are obvious (Fig. 145), no precise comparisons with the Zebrin pattern have been made. Our knowledge of the cortico-vestibular and nuclear projection of the caudal vermis, therefore, is still deficient. Progress can be expected from anatomical and electrophysiological studies using the Zebrin pattern as a reference. 

The projections of the Purkinje cells of the VF-SOCP-innervated x and b zones were verified by Andersson and Oscarsson (1978a) and Trott and Armstrong (1987a,b) and were found to correspond to the anatomical corticonuclear projection zones X and... 

Buisseret-Delmas and Angaut (1989b, 1993) defined three D-zones in the lateral part of the anterior lobe on the basis of their corticonuclear projection to the dorsolateral hump (Do), the dorsal magnocellular part of the lateral cerebellar nucleus (D,) and the ventral parvicellular part of this nucleus (Dj). They receive their olivocerebellar projections, respectively, from the DM group and the medial half of the ventral leaf of the PO (Do), the dorsal leaf of the PO (D,) and the lateral half of the ventral leaf of the PO (D2) (see Fig. 141). 

In the anterograde axonal tracing studies of Tan et al. (1995b) in the rabbit the olivocerebellar projection was matched with the white matter compartmentalization in adjacent AChE-stained sections and, consequently, with the corticovestibular and corticonuclear projection of the corresponding zones (Fig. 188) (see Section 6.1.5.). The medial and central compartments 4 and 2 contained fibers from the caudal DC and the more laterally located compartments 3 and 1 conducted fibers from the rostral DC and the VLO to corresponding zones in the molecular layer. The fifth, most lateral compartment contained fibers of the rostral MAO to the C2 zone. The rostral DC and VLO... 

Armstrong DM, Schild RF (1978b) An investigation of the cerebellar corticonuclear projections in the rat using an autoradiographic tracing method. II. Projections from the hemisphere. Brain Res., 141,235-249. 

Bangma GC, Ten Donkelaar HJ, Pellegrino A (1983) Cerebellar corticonuclear projections in the redeared turtle, Pseudemys scripta elegans. J. Comp. Neurol., 215, 258-274. 

Brodal A, Courville J (1973) Cerebellar corticonuclear projection in the cat. Crus II. An experimental study with silver methods. Brain Res., 50, 1-23. 

Courville J, Faraco-Cantin F (1976) Cerebellar corticonuclear projection demonstrated by the horseradish... 

Goodman DC, Hallett RE, Welch RB (1963) Patterns of localization in the cerebellar corticonuclear projections of the albino rat. J. Comp. Neurol, 121, 51-67. 

Trott JR, Armstrong DM (1987a) The cerebellar corticonuclear projection from lobule Vb/c of the cat anterior lobe a combined electrophysiological and autoradiographic study. II. Projections from the vermis. Exp. Brain. Res., 68. 339-354. 

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