Funding agencies: This study was supported by grants from the Guarantors of Brain Clinical Fellowship Scheme (AS) and the Japan Society for the Promotion of Science Postdoctoral Fellowships for Research Abroad (MH).
Cerebellar stimulation fails to modulate motor cortex plasticity in writing dystonia
Article first published online: 5 MAY 2014
© 2014 International Parkinson and Movement Disorder Society
Volume 29, Issue 10, pages 1304–1307, September 2014
How to Cite
Sadnicka, A., Hamada, M., Bhatia, K. P., Rothwell, J. C. and Edwards, M. J. (2014), Cerebellar stimulation fails to modulate motor cortex plasticity in writing dystonia. Mov. Disord., 29: 1304–1307. doi: 10.1002/mds.25881
Relevant conflicts of interest/financial disclosures: Nothing to report.
Full financial disclosures and author roles may be found in the online version of this article.
- Issue published online: 10 SEP 2014
- Article first published online: 5 MAY 2014
- Manuscript Accepted: 17 FEB 2014
- Manuscript Revised: 4 FEB 2014
- Manuscript Received: 16 SEP 2013
- writing dystonia;
- writers' cramp;
- cerebellar stimulation
Primary dystonia is characterized neurophysiologically by reduced inhibitory mechanisms and abnormal regulation of plasticity responses. The potential of anodal cerebellar transcranial direct current stimulation as a therapeutic tool in writing dystonia was examined, after the observation that cerebellar stimulation reduces responses to an associative plasticity protocol in healthy subjects.
Ten patients with writing dystonia completed a two-part study (sham and anodal) in which cerebellar stimulation was given simultaneously with paired associative stimulation. Electrophysiological and clinical parameters were measured before and after stimulation.
Clinical symptoms were unchanged by cerebellar stimulation. Patients exhibited much variability in the size and direction of their plasticity responses. Excessive or topographically abnormal plasticity responses were not observed. In the subgroup of patients with facilitatory responses to paired associative stimulation in the sham condition, anodal cerebellar stimulation retained its ability to reduce the magnitude of plasticity response.
Our limited understanding of intersubject variability of plasticity responses in writing dystonia currently undermines cerebellar stimulation as a novel treatment in this subset of dystonia. Cerebellar stimulation may be beneficial in other neurological disorders with consistently exaggerated plasticity. © 2014 International Parkinson and Movement Disorder Society