Cerebellar commissure

The AChE-banding pattern in the molecular layer of the anterior vermis and the white matter compartments of the anterior lobe continue, across the primary fissure, into the posterior lobe. A wide A compartment, flanked by diverging X and B compartments is present in the vermis of the simple lobule (Figs 119 and 120). The B compartment ends at the area without cortex in the center of the ansiform lobule, where it abuts on the pontocerebellar fibers of the cerebellar commissure that reach the surface at this point. It is not clear whether the X compartment continues from the simple lobule into lobule... 

Fig. 198. Diagram of the restiform body and middle cerebellar peduncle and their contributions to the cerebellar commissure. The dorsal spinocerebellar tract (DST) is part of the restiform body the ventral spinocerebellar tract (VST) enters the cerebellum after passing rostral to the trigeminal nerve. Voogd (1967).

Abbreviations Al = primary auditory area ac = anterior commissure Acc = accumbens nucleus AON = anterior olfactory nucleus BF = barrel field BLA = basolateral nucleus of the amygdala CAl = cornu ammonis 1 CA3 = cornu ammonis 3 cc = corpus callosum Cg = cingulate area CPu = caudate-putamen DCb = deep cerebellar nuclei DCo = dorsal cochlear nucleus DG = dentate gyrus DMV = dorsal motor nucleus of the vagus nerve ECu = external cuneate nucleus EP = external plexiform layer ER = entorhinal cortex f = fornix Fa = facial nucleus fa = facial nerve fr = fasciculus retroflexus G1 = glomerular layer GPe = (external segment of the)... 

The (central) cerebellar nuclei and the lateral vestibular nucleus of Deiters receive the axons of the Purkinje cells of the cerebellar cortex and serve as the main output stations of the cerebellum. The vermis and the flocculus also project to other vestibular nuclei, but here the Purkinje cell axons compete with vestibular root fibers, intrinsic and commissural vestibular connections and projections from the medial cerebellar nucleus and, therefore, are not the dominant afferent system. 

Aspartate is closely related metabolically and chemically to glutamate. In many respects it is difficult to differentiate between aspartate and glutamate as neurotransmitter candidates (Fonnum, 1984). There are, however, some fibers and terminals in which aspartate is regarded as a stronger transmitter candidate than glutamate. These include the cerebellar climbing fibers (Wiklund et al., 1982), hippocampal commissural fibers (Nadler et al., 1978), olfactory tract (Collins and Probett, 1981), cochlear nucleus afferents (Wenthold, 1979), and spinal cord intemeurons (Davidoff et al., 1967)... 

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