Origin and termination of cuneocerebellar tract
The origin and termination was determined for cells belonging to the cuneocerebellar tract in the cat, which consists of one proprioceptive component (P-CCT) activated by group I muscle afferents and one exteroceptive component (E-CCT) activated by cutaneous afferents. The recording sites of the cells were histologically verified and the termination of the axons assessed by antidromic activation from the cerebellar surface.
The P-CCT originates from cells in the external cuneate nucleus, where forelimb muscles are somatotopically represented. The observations suggest that practically all cells in this nucleus project to the cerebellum and are activated by muscle afferents.
The E-CCT originates from cells in the rostral part of the main cuneate nucleus, where they occur intermingled with lemniscal neurones.
The CCT terminates in the pars intermedia of lobule V of the anterior lobe and in the four rostral folia of the paramedian lobule. The majority of the cells send one branch to each projection area.
The P-CCT and E-CCT terminate in the same projection areas.
CCT neurones activated from distal and proximal parts of the limb terminate diffusely in the entire projection area, although there is some tendency for neurones activated from distal parts to terminate caudally and for neurones activated from proximal parts to terminate rostrally.
Key WordsCuneocerebellar tract External cuneate nucleus Main cuneate nucleus Cerebellum Cat
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- Adrian, E.D.: Afferent areas in the cerebellum connected with the limbs. Brain 66, 289–315 (1943).Google Scholar
- Andersen, P., Eccles, J.C., Schmidt, R.F., Yokota, T.: Identification of relay cells and interneurones in the cuneate nucleus. J. Neurophysiol. 27, 1080–1095 (1964).Google Scholar
- Armstrong, D.M., Harvey, R.J., Schild, R.F.: Distribution in the anterior lobe of the cerebellum of branches from climbing fibres to the paramedian lobule. Brain Res. 25, 203–206 (1971).Google Scholar
- Berman, A.L.: The brain stem of the cat. The University of Wisconsin Press, 1968.Google Scholar
- Bloedel, J.R., Burton, J.E.: Electrophysiological evidence for a mossy fiber input to the cerebellar cortex activated indirectly by collaterals of spinocerebellar pathways. J. Neurophysiol. 33, 308–320 (1970).Google Scholar
- Brodal, A.: Die Verbindungen des Nucleus cuneatus externus mit dem Kleinhirn beim Kaninchen und bei der Katze. Experimentelle Untersuchungen. Z. ges. Neurol. Psychiat. 171, 167–199 (1941).Google Scholar
- Burke, R., Lundberg, A., Weight, F.: Spinal border cell origin of the ventral spinocerebellar tract. Exp. Brain Res. 12, 283–294 (1971).Google Scholar
- Cooke, J.D., Larson, B., Oscarsson, O., Sjölund, B.: Origin and termination of the cuneocerebellar tract in the cat. Acta physiol. scand. 79, 32A-33A (1970).Google Scholar
- —: Organization of afferent connections to cuneocerebellar tract. Exp. Brain Res. 13, 359–377 (1971).Google Scholar
- Darian-Smith, I., Phillips, G., Ryan, R.D.: Functional organization in the trigeminal main sensory and rostral spinal nuclei of the cat. J. Physiol. (Lond.) 168, 129–146 (1963).Google Scholar
- Dow, R.S., Moruzzi, G.: The physiology and pathology of the cerebellum. Minneapolis: The University of Minnesota Press 1958.Google Scholar
- Ekerot, C.-F., Larson, B.: Differential termination of the proprioceptive and exteroceptive components of cuneocerebellar tract. Brain Res. (In press) (1971).Google Scholar
- Faber, D.S., Murphy, J.T.: Axonal branching in the climbing fiber pathway to the cerebellum. Brain Res. 15, 262–267 (1969).Google Scholar
- Ferraro, A., Barrera, S.E.: The nuclei of the posterior funiculi in Macacus Rhesus. An anatomic and experimental investigation. Arch. Neurol. Psychiat. (Chic.) 33, 262–275 (1935).Google Scholar
- Grant, G.: Projection of the external cuneate nucleus onto the cerebellum in the cat: An experimental study using silver methods. Exp. Neurol. 5, 179–195 (1962a).Google Scholar
- - Spinal course and somatotopically localized termination of the spinocerebellar tracts. An experimental study in the eat. Acta physiol. scand. 56, Suppl. 193 (1962b).Google Scholar
- Holmqvist, B., Oscarsson, O., Rosén, I.: Functional organization of the cuneocerebellar tract in the cat. Acta physiol. scand. 58, 216–235 (1963).Google Scholar
- Jansen, J., Brodal, A.: Handbuch der mikroskopischen Anatomie des Menschen, IV/8, Das Kleinhirn. Berlin-Göttingen-Heidelberg: Springer 1958.Google Scholar
- Johnson, J.I., Jr., Welker, W.I., Pubols, B.H., Jr.: Somatotopic organization of racoon dorsal column nuclei. J. comp. Neurol. 132, 1–44 (1968).Google Scholar
- Klüver, H., Barrera, E.: A method for the combined staining of cells and fibers in the nervous system. J. Neuropath. exp. Neurol. 12, 400–403 (1953).Google Scholar
- Kuypers, H.G.J.M., Tuerk, J.D.: The distribution of the cortical fibres within the nuclei cuneatus and gracilis in the cat. J. Anat. (Lond.) 98, 143–162 (1964).Google Scholar
- Körlin, D., Larson, B.: Differences in cerebellar potentials evoked by the group I and cutaneous components of the cuneocerebellar tract. Fifth International Meeting of Neurobiologists. Excitatory Synaptic Mechanisms, pp. 237–241. Ed. by P. Andersen and J. Jansen. Oslo: Universitetsforlaget 1970.Google Scholar
- Larson, B., Miller, S., Oscarsson, O.: Termination and functional organization of the dorsolateral spino-olivocerebellar path. J. Physiol. (Lond.) 203, 611–640 (1969).Google Scholar
- Lundherg, A., Oscarsson, O.: Functional organization of the dorsal spino-cerebellar tract in the cat. VII. Identification of units by antidromic activation from the cerebellar cortex with recognition of five functional subdivisions. Acta physiol. scand. 50, 356–374 (1960).Google Scholar
- —: Functional organization of the ventral spino-cerebellar tract in the cat. IV. Identification of units by antidromic activation from the cerebellar cortex. Acta physiol. scand. 54, 252–269 (1962).Google Scholar
- Miller, S., Oscarsson, O.: Termination and functional organization of spinoolivocerebellar paths. The Cerebellum in Health and Disease, pp. 172–200. Ed. by W.S. Fields and W.D. Willis. St. Louis: Warren H. Green 1970.Google Scholar
- Oscarsson, O.: Functional organization of the spino and cuneocerebellar tracts. Physiol. Rev. 45, 495–522 (1965).Google Scholar
- —: Functional significance of information channels from the spinal cord to the cerebellum. Neurophysiological Basis of Normal and Abnormal Motor Activities. 3rd Symposium of the Parkinson's Disease Information and Research Center, pp. 93–117. Ed. by M.D. Yahr and D.P. Purpura. Hewlett, N.Y.: Raven Press 1967.Google Scholar
- —: The sagittal organization of the cerebellar anterior lobe as revealed by the projection patterns of the climbing fiber system. Neurobiology of Cerebellar Evolution and Development, pp. 525–537. Ed. by R. Llinas. Chicago: American Medical Association 1969.Google Scholar
- —: Functional organization of spinocerebellar paths. Handbook of Sensory Physiology. Vol. II. Somatosensory System. Ed. by A. Iggo. Berlin-Heidelberg-New York: Springer, in press 1971.Google Scholar
- —, Uddenberg, N.: Identification of a spinocerebellar tract activated from forelimb afferents in the cat. Acta physiol. scand. 62, 125–136 (1964).Google Scholar
- —: Properties of afferent connections to the rostral spinocerebellar tract in the cat. Acta physiol. scand. 64, 143–153 (1965).Google Scholar
- Reighard, J., Jennings, H.S.: Anatomy of the cat. Henry Holt and Company, INC. 3rd edition. New York, 1935.Google Scholar
- Rosén, I.: Localization in caudal brain stem and cervical spinal cord of neurones activated from forelimb group I afferents in the cat. Brain Res. 16, 55–71 (1969).Google Scholar
- —, Sjölund, B.: Natural stimulation of group I activated cells in the cuneate nuclei of the cat. Acta physiol. scand. Suppl. 330, 118 (1969).Google Scholar
- Thach, W.T.: Somatosensory receptive fields of single units in cat cerebellar cortex. J. Neurophysiol. 30, 675–696 (1967).Google Scholar
- Verhaart, W.J.C.: A Sterotactic Atlas of the Brain Stem of the Cat. Assen: Van Gorcum & Comp. 1964.Google Scholar
- Voogd, J.: The importance of fiber connections in the comparative anatomy of the mammalian cerebellum. Neurobiology of Cerebellar Evolution and Development, pp. 493–514. Ed. by R. Llinas. Chicago: American Medical Association 1969.Google Scholar