| 1. |
- Asanuma, H., et al.
(författare)
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Projection of individual pyramidal tract neurons to lumbar motor nuclei of the monkey
- 1979
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Ingår i: Experimental Brain Research. - 0014-4819 .- 1432-1106. ; 34, s. 73-89
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Tidskriftsartikel (refereegranskat)abstract
- The projection of individual pyramidal tract (PT) neurons from the hindlimb area in the precentral gyrus of the cerebral cortex to the lumbar spinal cord was studied in the monkey by systematically searching for sites within identified regions of the spinal gray from which the PT neurons could be antidromically activated by local stimulation. All investigated neurons belonged to the fast conducting fraction of PT neurons. The following results were obtained. 1. Each PT neuron could be activated from more than one region of the spinal gray matter, including identified spinal motor nuclei and areas dorsomedial to these nuclei, but not the intermediate nucleus or regions dorsal to it. "Passage areas" and "termination areas" were defined. 2. Half of the PT neurons with termination areas within motor nuclei had these areas in more than one nucleus. There were thus strong suggestions for synaptic contacts of some PT neurons with motoneurons of more than one muscle. 3. Four groups of three or four neurons were recorded simultaneously by the same cortical electrode. Comparisons of passage and termination areas within groups revealed both similarities and differences in projections of neighboring neurons. Every neuron was activated from some region(s) where others of the group were not. Common passage areas, or passage and termination areas, for two or three neurons of a group within at least one motor nucleus were found for all groups. Termination areas in the same motor nucleus have been found for the majority of the neurons of only one group. These common projection areas are compatible with, but do not prove, that a group of adjacent PT neurons has common target cells in the spinal cord. © 1979 Springer-Verlag.
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| 2. |
- Bjursten, Lars Magnus, et al.
(författare)
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Behavioural repertory of cats without cerebral cortex from infancy
- 1976
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Ingår i: Experimental Brain Research. - 0014-4819. ; 25:2, s. 115-130
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Tidskriftsartikel (refereegranskat)abstract
- Bilateral removal of the cerebral cortex was made in cats neonatally. Spontaneous and imposed behaviour was studied while they were growing up and after they had become adult. Special emphasis was put on the utilization of visual cues and on learning. The cats ate, drank and groomed themselves adequately. Adequate maternal and female sexual behaviour was observed. They utilized the visual and haptic senses with respect to external space. Two cats were trained to perform visual discrimination if a T-maze. The adequacy of the behaviour of these cats is compared to that of animals with similar lesions made at maturity.
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| 3. |
- Liedgren, Christer, et al.
(författare)
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Projection of thalamic neurons to cat primary vestibular cortical fields studied by means of retrograde axonal transport of horseradish peroxidase
- 1976
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Ingår i: Experimental Brain Research. - : Springer. - 0014-4819 .- 1432-1106. ; 24:3, s. 237-243
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Tidskriftsartikel (refereegranskat)abstract
- The two vestibular cortical projection areas in the anterior suprasylvian sulcus and post-cruciate dimple regions were defined by evoked potential technique in anaesthetized cats. The thalamic location of neurons with axon terminals in these fields was determined using the method of retrograde axonal transport of horseradish peroxidase. The ascending vestibular pathway appeared to be separated also at the thalamic level, where cells in the ventro-posterolateral nucleus were found to project to the post cruciate dimple and cells in the posterior nuclear group to the anterior suprasylvian vestibular cortical fields.
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| 4. |
- Ödkvist, Lars, et al.
(författare)
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Vestibular and somatosensory inflow to the vestibular projection area in the post cruciate dimple region of the gat cerebral cortex
- 1975
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Ingår i: Experimental Brain Research. - : Springer. - 0014-4819 .- 1432-1106. ; 22:2, s. 185-196
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Tidskriftsartikel (refereegranskat)abstract
- In anesthetized cats 251 cells within the cortical vestibular projection area, adjacent to the post-cruciate dimple, were analyzed as to their input characteristics employing extracellular recording techniques. The post cruciate dimple vestibular field, which is located in area 3a, has a high degree of convergence between vestibular and peripheral somatosensory input. The latter is not restricted to muscle afferents but includes cutaneous modalities. The functional significance of this vestibular cortical projection field is discussed.
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