Hostname: page-component-84b7d79bbc-x5cpj Total loading time: 0 Render date: 2024-07-31T05:46:41.696Z Has data issue: false hasContentIssue false
  • English
  • Français

Manual Tracking Performance in Patients with Cerebellar Incoordination: Effects of Mechanical Loading

Published online by Cambridge University Press:  18 September 2015

Betty-Lynn Morrice ,
Werner J. Becker ,
J.A. Hoffer  and
Robert G. Lee
Betty-Lynn Morrice
Affiliation:
Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
Werner J. Becker
Affiliation:
Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
J.A. Hoffer
Affiliation:
Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
Robert G. Lee*
Affiliation:
Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
*
Department of Clinical Neurosciences, Foothills Hospital, 1403 - 29th Street N.W., Calgary, Alberta, Canada T2N 2T9
Rights & Permissions [Opens in a new window]

Abstract:

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Manual tracking performance was studied in five patients with cerebellar incoordination due to unilateral cerebellar hemisphere lesions. The subjects were required to track a target on an oscilloscope screen by moving a cursor controlled by flexion-extension movements of the wrist. In comparison to normal subjects, the cerebellar patients, using their clinically affected arm, demonstrated irregular tracking patterns with inappropriate accelerations and decelerations, numerous high velocity peaks of movement, and an increased time lag between the cursor and the target.

The addition of a viscous load provided by feeding back wrist velocity to a torque motor coupled to the apparatus resulted in significant improvement in tracking performance and suppression of the high velocity peaks. Increasing elastic stiffness by feeding back wrist position or inertial load by adding weights to the hand did not improve performance on this task. It is proposed that a hypotonic cerebellar limb behaves like an underdamped mechanical system. The addition of viscous loads helps restore more normal damping during voluntary movements of the arm.

Résumé:

RÉSUMÉ:

La poursuite manuelle a été étudiée chez cinq patients atteints d'incoordination cérébelleuse due à des lésions unilatérales d'un hémisphère cérébelleux. Les sujets devaient poursuivre une cible sur un écran d'oscilloscope en déplaçant un curseur contrôlé par des mouvements de flexion et d'extension du poignet. Par rapport à des sujets normaux, les patients avec atteinte cérébelleuse exécutaient des tracés de poursuite irréguliers avec des accélérations et décélérations inappropriées, de nombreuses pointes de mouvement de haute vélocité et une augmentation du délai entre le curseur et la cible. L'ajout d'une charge visqueuse, provenant de la vélocité du poignet agissant sur un moteur couplé à l'appareillage, a résulté en une amélioration significative dans l'exécution de la poursuite et une suppression des pointes de haute vélocité. Ni une augmentation de la rigidité élastique produite par la localisation de la position du poignet, ni une augmentation de la charge d'inertie produite par l'ajout de poids à la main n'ont amélioré l'exécution de la tâche. Nous proposons qu'un membre présentant une hypotonie cérébelleuse se comporte comme un système mécanique sous-amorti. L'addition de charges visqueuses aide à rétablir un amortissement plus normal pendant les mouvements volontaires du bras.

Type
Original Articles
Information
Canadian Journal of Neurological Sciences , Volume 17 , Issue 3 , August 1990 , pp. 275 - 285
Copyright
Copyright © Canadian Neurological Sciences Federation 1990

References

REFERENCES

1. Holmes, G. The symptoms of acute cerebellar injuries due to gunshot injuries. Brain 1917; 40: 461–535.Google Scholar
2. Holmes, G. The cerebellum of man. Brain 1939; 62: 1–30.Google Scholar
3. Beppu, H, Suda, M, Tanaka, R. Analysis of cerebellar motor disorders by visually-guided elbow tracking movements. Brain 1984; 107: 787–809.Google Scholar
4. Beppu, H, Nagaoka, M, Tanaka, R. Analysis of cerebellar motor disorders by visually-guided elbow tracking movements: 2. Contribution of the visual cues on slow ramp pursuit. Brain 1987; 110: 1–18.Google Scholar
5. Sanes, JN, LeWitt, PA, Mauritz, KH. Visual and mechanical control of postural and kinetic tremor in cerebellar system disorders. J Neurol Neurosurg Psychiatry 1988; 51: 934–943.Google Scholar
6. Zee, DS, Yee, RD, Gogan, DG, et al. Ocular motor abnormalities in hereditary cerebellar ataxia. Brain 1976; 99: 207–234.Google Scholar
7. Brooks, VB, Thach, WT. Cerebellar control of posture and movement. In: Brookhart, , Mountcastle, , Brooks, , Greiger, , eds. Handbook of Physiology, Section 1, The Nervous System. American Physiological Society. (Bethesda, Maryland) 1981; 877–946. Google Scholar
8. Miall, RC, Weir, DJ, Stein, JF. Visuo-motor tracking during reversible inactivation of the cerebellum. Exp Brain Research 1987; 65: 455–464.Google Scholar
9. Miall, RC, Weir, DJ, Stein, JF. Manual tracking of visual targets by trained monkeys. Behav Brain Res 1986; 20: 185–201.Google Scholar
10. Vilis, T, Hore, J, Effects of changes in mechanical state of limb on cerebellar intention tremor. J Neurophysiol 1977; 40: 1213–1224.Google Scholar
11. Homberg, V, Hefter, H, Reiners, K, et al. Differential effects of changes of mechanical limb properties on physiological and pathological tremor. J Neurol Neurosurg Psychiatry 1987; 50: 568–579.Google Scholar
12. Lacquaniti, F, Licata, F, Soechting, JF. The mechanical behavior of the human forearm in response to transient perturbations. Biol Cybern 1982; 44: 35–46.Google Scholar
13. Stein, RB, Lee, RG. Tremor and clonus. In: Brookhart, , Mountcastle, , Brooks, , Geiger, , eds. Handbook of Physiology, Section I. The Nervous System, chap. 9. American Physiological Society. (Bethesda, Maryland) 1981; 325–343.Google Scholar
14. Akazawa, K, Milner, TE, Stein, RB. Modulation of reflex EMG and stiffness in response to stretch of human finger muscle. J Neurophysiol 1983; 49: 16–27.Google Scholar
15. Hasan, Z. Optimized movement trajectories and joint stiffness in unperturbed, inertially loaded movements. Biol Cybern 1986; 53: 373–382.Google Scholar
16. Schieber, MH, Thach, WT. Trained slow tracking. II. Bidirectional discharge patterns of cerebellar nuclear, motor cortex, and spindle afferent neurons. J Neurophysiol 1985; 54: 1228–1270.Google Scholar
17. Smith, AM. The coactivation of antagonist muscles. Can J Physiol Pharmacol 1981; 59: 733–747.Google Scholar
18. Glickstein, M, May, JG III, Mercier, BE. Corticopontine projection in the macaque: the distribution of labelled cortical cells after large injections of horseradish peroxidase in the pontine nuclei. J Comp Neurol 1985; 235: 343–359.Google Scholar
19. Miller, RG, Freund, HJ. Cerebellar dyssynergia in humans – a quantitative analysis. Ann Neurol 1980; 8: 574–579.Google Scholar
20. Flament, D, Vilis, T, Hore, J. Dependence of cerebellar tremor on proprioceptive but not visual feedback. Exp Neurol 1984; 84: 314–325.Google Scholar
21. Hewer, RL, Cooper, R, Morgan, MH. An investigation into the value of treating intention tremor by weighting the affected limb. Brain 1972; 95: 579–590.Google Scholar
22. Morgan, MH, Hewer, RL, Cooper, R. Application of an objective method of assessing intention tremor – a further study on the use of weights to reduce intention tremor. J Neurol Neurosurg Psychiatry 1975; 38: 259–264.Google Scholar