Topic
Interposed nucleus
About: Interposed nucleus is a research topic. Over the lifetime, 47 publications have been published within this topic receiving 3050 citations.
Papers
Book•
1 Sep 2014
TL;DR: The investigations reported here are virtually without antecedents, a refreshing change from the cerebellar cortex which has been repeatedly and exhaustively surveyed.
Abstract: Recent physiologic investigations have shown that the deep cerebellar nuclei may play an important role in the initiation and monitoring of skilled move- ments. Much of this physiologic work has been carried out in the absence of a secure foundation in neuroanatomical information. Although the main sources of the afferent fibers and the major terminations of the efferent fibers related to these nuclei have been known for many years, remarkably little information about the organization of the nuclei themselves has been collected. The kinds of nerve cells, their arrangement within the nuclei, the patterns of their dendritic arborizations, the distribution of incoming fibers among the neurons, the relationship between the outgoing nerve fibers and the nerve cells from which they originate - these and many other morphologic features were either unknown or only superficially explored. In fact, so little was known about the deep cerebellar nuclei when I began to work on this subject that the investigations reported here are virtually without antecedents, a refreshing change from the cerebellar cortex which has been repeatedly and exhaustively surveyed. My studies on the cerebellar nuclei began in the spring of 1972. They were initiated with the intent of applying the principles of analysis that had been developed for the cerebellar cortex to a different but related part of the brain.
653 citations
TL;DR: After lesions of inferior olive, survival times of 5 to 12 days and Nauta staining, degeneration is present in white matter and central cerebellar nuclei and Deiters' nucleus andOccasional labeling of mossy fiber terminals is explained by involvement of reticular nuclei.
Abstract: After lesions of inferior olive, survival times of 5 to 12 days and Nauta staining, degeneration is present in white matter and central cerebellar nuclei and Deiters' nucleus. Shorter survival times from 40 to 60 hours and Fink-Heimer impregnation reveal degenerating climbing fiber terminals in the molecular layer. With 3H-leucine autoradiography and survival times of three to seven days the entire trajectory of the climbing fibers can be traced. Olivocerebellar fibers cross in the brain stem and terminate contralaterally in cortex and central nuclei. Occasional labeling of mossy fiber terminals is explained by involvement of reticular nuclei.
Small parts of the inferior olive connect with narrow longitudinal zones in the cortex through compartments in the white matter. The corresponding distribution of olivocerebellar fibers and Purkinje cell axons over these compartments suggests that the organization of the olivocerebellar and corticonuclear projection is essentially similar. Collaterals always terminate in the central cerebellar necleus which receives a corticonuclear projection from the zone in which the parent fibers terminate.
Caudal medial accessory olive projects to medial vermal zone A and to fastigial nucleus, subnucleus beta projecting to lobule VII and caudal fastigial nucleus. Cadual dorsal accessory olive projects to lateral vermal zone B in lobules I-VI, Deiters' nucleus and dorsomedial subnucleus of interposed nucleus. The caudal principal olive (dorsal cap, ventrolateral outgrowth receiving visual and vestibular input) projects to flocculo-nodular lobe.
593 citations
TL;DR: The data show that the excitatory nucleocortical closed-loop circuitry of the cerebellum relays a corollary discharge of premotor signals and suggests an amplifying role of this circuitry in controlling associative motor learning.
163 citations
TL;DR: The topographic organization of afferent projections from the deep cerebellar nuclei, medulla oblongata and spinal cord to the paramedian reticular nucleus (PRN) of the cat was studied using the horseradish peroxidase (HRP) method of retrograde labelling to provide the neuroanatomical substrate for a better understanding of the functional role of the PRN in mediating cardiovascular responses appropriate to postural changes.
150 citations
TL;DR: Electromyographic study allowed us to investigate the motor response latencies and the modality of cerebellar control on musculature and the effects of the interposed and dentate nucleus appear to be equally distributed among flexor and extensor muscles.
Abstract: Movements elicited by the stimulation of the cerebellar nuclei were studied in alert baboons chronically prepared. The motor responses were filmed and recorded in eight muscles through chronically implanted electrodes. Two types of motor effects were observed: (1) Simple movements that concerned the unidirectional displacement of a limb segment. (2) Complex movements that involved distinct and frequently noncontiguous muscles were stereotyped and could not be dissociated. These movements are defined as motor synergies. Electromyographic study allowed us to investigate the motor response latencies and the modality of cerebellar control on musculature. Simple movements were due to the activation of muscles within the involved segment in addition to the co-contraction of muscles of a nearby segment. Thus they could be due to a cerebellar control over muscular synergies. Complex movements would correspond to the simultaneous activation of distinct muscular groups and could also be the outcome of a cerebellar control on motor synergies. Thus the effects of the interposed nucleus concern preferably flexor muscles whereas the effects of the dentate nucleus appear to be equally distributed among flexor and extensor muscles. Somatotopic motor localization were evidenced both in the interposed and dentate nuclei: there are somatotopic relations between every region of the interposed nucleus and musculature. As regards the dentate nucleus, two subdivisions were distinguished according to the complexity of elicited motor effects: (A) an antero-medial region from which motor synergies can be elicited. (B) a postero-lateral region giving rise to simple movements, mainly hand movements.
133 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 4 |
| 2019 | 2 |
| 2017 | 1 |
| 2016 | 2 |
| 2015 | 4 |
| 2014 | 2 |