Author:
Matsugi Akiyoshi,Nishishita Satoru,Bando Kyota,Kikuchi Yutaka,Tsujimoto Keigo,Tanabe Yuto,Yoshida Naoki,Tanaka Hiroaki,Douchi Shinya,Honda Takeru,Odagaki Masato,Nakano Hideki,Okada Yohei,Mori Nobuhiko,Hosomi Koichi
Abstract
AbstractThis study aimed to investigate abnormalities in inhibitory cortical excitability and motor control during ballistic-targeting movements in individuals with degenerative cerebellar ataxia (DCA). Sixteen participants took part in the study (DCA group [n = 8] and healthy group [n = 8]). The resting motor-threshold and cortical silent period (cSP) were measured in the right-hand muscle using transcranial magnetic stimulation over the left primary motor cortex. Moreover, the performance of the ballistic-targeting task with right wrist movements was measured. The Scale for the Assessment and Rating of Ataxia was used to evaluate the severity of ataxia. The results indicated that the cSP was significantly longer in participants with DCA compared to that in healthy controls. However, there was no correlation between cSP and severity of ataxia. Furthermore, cSP was linked to the ballistic-targeting task performance in healthy participants but not in participants with DCA. These findings suggest that there is excessive activity in the gamma-aminobutyric acid-mediated cortical inhibitory circuit in individuals with DCA. However, this increase in inhibitory activity not only fails to contribute to the control of ballistic-targeting movement but also shows no correlation with the severity of ataxia. These imply that increased excitability in inhibitory cortical circuits in the DCA may not contribute the motor control as much as it does in healthy older adults under limitations associated with a small sample size. The study's results contribute to our understanding of motor control abnormalities in people with DCA and provide potential evidence for further research in this area.
Funder
Japan Society for the Promotion of Science
Publisher
Springer Science and Business Media LLC
Reference56 articles.
1. Coarelli, G. et al. The inherited cerebellar ataxias: An update. J. Neurol. 270, 208–222. https://doi.org/10.1007/s00415-022-11383-6 (2023).
2. Maas, R., Helmich, R. C. G. & van de Warrenburg, B. P. C. The role of the cerebellum in degenerative ataxias and essential tremor: Insights from noninvasive modulation of cerebellar activity. Mov. Disord. 35, 215–227. https://doi.org/10.1002/mds.27919 (2020).
3. Opal, P. & Ashizawa, T. in GeneReviews (R) (eds M. P. Adam et al.) (University of Washington, Seattle University of Washington, Seattle. GeneReviews is a registered trademark of the University of Washington, Seattle. All rights reserved., 1993).
4. Saucier, J., Al-Qadi, M., Amor, M. B., Ishikawa, K. & Chamard-Witkowski, L. Spinocerebellar ataxia type 31: A clinical and radiological literature review. J. Neurol. Sci. 444, 120527. https://doi.org/10.1016/j.jns.2022.120527 (2023).
5. Casey, H. L. & Gomez, C. M. in GeneReviews (R) (eds M. P. Adam et al.) (1993).