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Wolfram Tetzlaff - One of the best experts on this subject based on the ideXlab platform.
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proximal and distal impairments in rat forelimb use in reaching follow unilateral Pyramidal Tract lesions
Behavioural Brain Research, 1993Co-Authors: Ian Q Whishaw, Sergio M Pellis, Boguslaw Gorny, Bryan Kolb, Wolfram TetzlaffAbstract:AbsTract Although it was once thought that the corticospinal (Pyramidal) Tract was the main substrate of voluntary movement, the extent to which it is involved in the control of proximal vs. distal musculature, independent finger movements, and movements characteristic of different species of animals now is unclear. The objective of this study was to examine the effects of Pyramidal Tract lesions on skilled forelimb use in rats. In addition, cell morphology in motor cortex following lesions was examined. Naive and trained rats received unilateral Pyramidal sections just rostral to the Pyramidal decussation. Performance was assessed and filmed on two reaching tasks. Measures of reaching consisted of success in obtaining food, kinematic analysis of limb trajectory and velocity, and qualitative evaluation of 10 movement components comprising a reach. Pyramidal Tract lesions only impaired reaching for single food pellets. Almost all movements comprising a reach, except digit opening, were impaired, including lifting, aiming, pronating and supinating the limb, and releasing food. Although success in limb use was unchanged over the 180 day observation period, there were significant improvements in the qualitative features of limb use. Histologically, the morphology of Pyramidal cells in the forelimb area ipsilateral to the lesion seemed normal. Rats with additional damage to adjacent structures, such as the medial lemniscus and olivary complex, were much more severely impaired on the reaching tasks, and displayed similar impairments as judged by qualitative and kinematic measures. The results demonstrate that a number of movements involved in independent limb use are chronically impaired by Pyramidal Tract lesions in the rat. Nevertheless, significant use of the limb is possible, due perhaps to both the contribution of extraPyramidal motor systems and the influence of the remaining Pyramidal system through its extraPyramidal connections. The results not only show that the rat Pyramidal Tract supports functions very similar to those of primates and thus might provide a good model for some aspects of Pyramidal Tract dysfunctions, but also they argue that the Pyramidal Tract is involved in both proximal and distal limb movements.
Ian Q Whishaw - One of the best experts on this subject based on the ideXlab platform.
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proximal and distal impairments in rat forelimb use in reaching follow unilateral Pyramidal Tract lesions
Behavioural Brain Research, 1993Co-Authors: Ian Q Whishaw, Sergio M Pellis, Boguslaw Gorny, Bryan Kolb, Wolfram TetzlaffAbstract:AbsTract Although it was once thought that the corticospinal (Pyramidal) Tract was the main substrate of voluntary movement, the extent to which it is involved in the control of proximal vs. distal musculature, independent finger movements, and movements characteristic of different species of animals now is unclear. The objective of this study was to examine the effects of Pyramidal Tract lesions on skilled forelimb use in rats. In addition, cell morphology in motor cortex following lesions was examined. Naive and trained rats received unilateral Pyramidal sections just rostral to the Pyramidal decussation. Performance was assessed and filmed on two reaching tasks. Measures of reaching consisted of success in obtaining food, kinematic analysis of limb trajectory and velocity, and qualitative evaluation of 10 movement components comprising a reach. Pyramidal Tract lesions only impaired reaching for single food pellets. Almost all movements comprising a reach, except digit opening, were impaired, including lifting, aiming, pronating and supinating the limb, and releasing food. Although success in limb use was unchanged over the 180 day observation period, there were significant improvements in the qualitative features of limb use. Histologically, the morphology of Pyramidal cells in the forelimb area ipsilateral to the lesion seemed normal. Rats with additional damage to adjacent structures, such as the medial lemniscus and olivary complex, were much more severely impaired on the reaching tasks, and displayed similar impairments as judged by qualitative and kinematic measures. The results demonstrate that a number of movements involved in independent limb use are chronically impaired by Pyramidal Tract lesions in the rat. Nevertheless, significant use of the limb is possible, due perhaps to both the contribution of extraPyramidal motor systems and the influence of the remaining Pyramidal system through its extraPyramidal connections. The results not only show that the rat Pyramidal Tract supports functions very similar to those of primates and thus might provide a good model for some aspects of Pyramidal Tract dysfunctions, but also they argue that the Pyramidal Tract is involved in both proximal and distal limb movements.
E S Louwerse - One of the best experts on this subject based on the ideXlab platform.
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Images in clinical medicine. Wallerian degeneration of the Pyramidal Tract.
The New England journal of medicine, 1994Co-Authors: J A Dol, E S LouwerseAbstract:Figure 1. Wallerian Degeneration of the Pyramidal Tract. Coronal views of the brain of a 41-year-old man with the acquired immunodeficiency syndrome and right-sided spastic hemiplegia, aphasia, and hemianopia were obtained by magnetic resonance imaging (MRI) eight months after the patient had an intracerebral hemorrhage. The consecutive T2 weighted coronal MRI slices show the old hematoma as an irregular lesion, which is hypointense because of hemosiderin deposition; dilatation of the left lateral ventricle is also evident. In addition, a long band of increased signal intensity traces the anatomical course of the Pyramidal Tract from the lesion in the internal . . .
Hirohisa Watanabe - One of the best experts on this subject based on the ideXlab platform.
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Fractional anisotropy values detect Pyramidal Tract involvement in multiple system atrophy.
Journal of the Neurological Sciences, 2008Co-Authors: Hirohisa Watanabe, Naoki Atsuta, Jo Senda, Yoshinari Kawai, Fumiaki Tanaka, Shinji Naganawa, Hiroshi Fukatsu, SobueAbstract:AbsTract Objective Pathological studies have shown remarkable Pyramidal Tract involvement in multiple system atrophy (MSA), while clinical Pyramidal signs are relatively rare. We investigated the fractional anisotropy (FA) values to assess the degree of Pyramidal Tract involvement in MSA, in comparison with amyotrophic lateral sclerosis (ALS) and controls. Furthermore, we compared FA values between MSA patients with or without clinical Pyramidal signs and controls, and between MSA patients with or without positive conventional MRI findings and controls. Methods We evaluated FA values in the internal capsule, corona radiate and whole Pyramidal Tract using visualized Tractography of 65 subjects (20 probable MSA patients, 28 age-matched ALS patients, and 17 age-matched healthy controls) using a 3.0T magnetic resonance system. Results The FA values in the internal capsule, corona radiate, and whole Pyramidal Tract were significantly lower in MSA patients than in controls and were at a level similar to those of ALS patients. In addition, low FA values were prominent in MSA patients, even in those with short duration of illness, lacking precentral gyrus hyperintensity in FLAIR images, and without Pyramidal signs. Conclusion FA values could identify Pyramidal Tract degeneration even in patients with early phase MSA and those without clinical Pyramidal signs or abnormal MRI findings. More extensive degeneration of the Pyramidal Tract occurs in MSA than so far believed.
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Fractional anisotropy values detect Pyramidal Tract involvement in multiple system atrophy.
Journal of the neurological sciences, 2008Co-Authors: Hirohisa Watanabe, Naoki Atsuta, Jo Senda, Yoshinari Kawai, Fumiaki Tanaka, Shinji Naganawa, Hiroshi Fukatsu, Gen SobueAbstract:Pathological studies have shown remarkable Pyramidal Tract involvement in multiple system atrophy (MSA), while clinical Pyramidal signs are relatively rare. We investigated the fractional anisotropy (FA) values to assess the degree of Pyramidal Tract involvement in MSA, in comparison with amyotrophic lateral sclerosis (ALS) and controls. Furthermore, we compared FA values between MSA patients with or without clinical Pyramidal signs and controls, and between MSA patients with or without positive conventional MRI findings and controls. We evaluated FA values in the internal capsule, corona radiate and whole Pyramidal Tract using visualized Tractography of 65 subjects (20 probable MSA patients, 28 age-matched ALS patients, and 17 age-matched healthy controls) using a 3.0T magnetic resonance system. The FA values in the internal capsule, corona radiate, and whole Pyramidal Tract were significantly lower in MSA patients than in controls and were at a level similar to those of ALS patients. In addition, low FA values were prominent in MSA patients, even in those with short duration of illness, lacking precentral gyrus hyperintensity in FLAIR images, and without Pyramidal signs. FA values could identify Pyramidal Tract degeneration even in patients with early phase MSA and those without clinical Pyramidal signs or abnormal MRI findings. More extensive degeneration of the Pyramidal Tract occurs in MSA than so far believed.
Sergio M Pellis - One of the best experts on this subject based on the ideXlab platform.
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proximal and distal impairments in rat forelimb use in reaching follow unilateral Pyramidal Tract lesions
Behavioural Brain Research, 1993Co-Authors: Ian Q Whishaw, Sergio M Pellis, Boguslaw Gorny, Bryan Kolb, Wolfram TetzlaffAbstract:AbsTract Although it was once thought that the corticospinal (Pyramidal) Tract was the main substrate of voluntary movement, the extent to which it is involved in the control of proximal vs. distal musculature, independent finger movements, and movements characteristic of different species of animals now is unclear. The objective of this study was to examine the effects of Pyramidal Tract lesions on skilled forelimb use in rats. In addition, cell morphology in motor cortex following lesions was examined. Naive and trained rats received unilateral Pyramidal sections just rostral to the Pyramidal decussation. Performance was assessed and filmed on two reaching tasks. Measures of reaching consisted of success in obtaining food, kinematic analysis of limb trajectory and velocity, and qualitative evaluation of 10 movement components comprising a reach. Pyramidal Tract lesions only impaired reaching for single food pellets. Almost all movements comprising a reach, except digit opening, were impaired, including lifting, aiming, pronating and supinating the limb, and releasing food. Although success in limb use was unchanged over the 180 day observation period, there were significant improvements in the qualitative features of limb use. Histologically, the morphology of Pyramidal cells in the forelimb area ipsilateral to the lesion seemed normal. Rats with additional damage to adjacent structures, such as the medial lemniscus and olivary complex, were much more severely impaired on the reaching tasks, and displayed similar impairments as judged by qualitative and kinematic measures. The results demonstrate that a number of movements involved in independent limb use are chronically impaired by Pyramidal Tract lesions in the rat. Nevertheless, significant use of the limb is possible, due perhaps to both the contribution of extraPyramidal motor systems and the influence of the remaining Pyramidal system through its extraPyramidal connections. The results not only show that the rat Pyramidal Tract supports functions very similar to those of primates and thus might provide a good model for some aspects of Pyramidal Tract dysfunctions, but also they argue that the Pyramidal Tract is involved in both proximal and distal limb movements.
