Tactile and proprioceptive dysfunction differentiates cervical dystonia with and without tremor
Citation Manager Formats
Make Comment
See Comments

This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Abstract
Objective To determine whether different phenotypes of cervical dystonia (CD) express different types and levels of somatosensory impairment.
Methods We assessed somatosensory function in patients with CD with and without tremor (n = 12 each) and in healthy age-matched controls (n = 22) by measuring tactile temporal discrimination thresholds of the nondystonic forearm and proprioceptive acuity in both the dystonic (head/neck) and nondystonic body segments (forearm/hand) using a joint position‐matching task. The head or the wrist was passively displaced along different axes to distinct joint positions by the experimenter or through a robotic exoskeleton. Participants actively reproduced the experienced joint position, and the absolute joint position‐matching error between the target and the reproduced positions served as a marker of proprioceptive acuity.
Results Tactile temporal discrimination thresholds were significantly elevated in both CD subgroups compared to controls. Proprioceptive acuity of both the dystonic and nondystonic body segments was elevated in patients with CD and tremor with respect to both healthy controls and patients with CD without tremor. That is, tactile abnormalities were a shared dysfunction of both CD phenotypes, while proprioceptive dysfunction was observed in patients with CD with tremor.
Conclusions Our findings suggest that the pathophysiology in CD can be characterized by 2 abnormal neural processes: a dysfunctional somatosensory gating mechanism involving the basal ganglia that triggers involuntary muscle spasms and abnormal processing of proprioceptive information within a defective corticocerebellar loop, likely affecting the feedback and feedforward control of head positioning. This dysfunction is expressed mainly in CD with tremor.
Glossary
- Abd/Add=
- abduction/adduction;
- CD=
- cervical dystonia;
- CD-NT=
- cervical dystonia without tremor;
- CD-T=
- cervical dystonia with tremor;
- Flex/Ext=
- flexion/extension;
- HC=
- healthy controls;
- ISI=
- interstimulus interval;
- PAI=
- proprioceptive acuity index;
- PS=
- pronation/supination;
- RM-ANCOVA=
- repeated-measures analysis of covariance;
- RoM=
- range of motion;
- TDt=
- temporal discrimination thresholds
Footnotes
Go to Neurology.org/N for full disclosures. Funding information and disclosures deemed relevant by the authors, if any, are provided at the end of the article.
↵* These authors contributed equally to this work.
Editorial, page 243
- Received May 16, 2019.
- Accepted in final form August 28, 2019.
- © 2020 American Academy of Neurology
AAN Members
We have changed the login procedure to improve access between AAN.com and the Neurology journals. If you are experiencing issues, please log out of AAN.com and clear history and cookies. (For instructions by browser, please click the instruction pages below). After clearing, choose preferred Journal and select login for AAN Members. You will be redirected to a login page where you can log in with your AAN ID number and password. When you are returned to the Journal, your name should appear at the top right of the page.
AAN Non-Member Subscribers
Purchase access
For assistance, please contact:
AAN Members (800) 879-1960 or (612) 928-6000 (International)
Non-AAN Member subscribers (800) 638-3030 or (301) 223-2300 option 3, select 1 (international)
Sign Up
Information on how to subscribe to Neurology and Neurology: Clinical Practice can be found here
Purchase
Individual access to articles is available through the Add to Cart option on the article page. Access for 1 day (from the computer you are currently using) is US$ 39.00. Pay-per-view content is for the use of the payee only, and content may not be further distributed by print or electronic means. The payee may view, download, and/or print the article for his/her personal, scholarly, research, and educational use. Distributing copies (electronic or otherwise) of the article is not allowed.
Letters: Rapid online correspondence
REQUIREMENTS
You must ensure that your Disclosures have been updated within the previous six months. Please go to our Submission Site to add or update your Disclosure information.
Your co-authors must send a completed Publishing Agreement Form to Neurology Staff (not necessary for the lead/corresponding author as the form below will suffice) before you upload your comment.
If you are responding to a comment that was written about an article you originally authored:
You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid
and apply to letter.
Submission specifications:
- Submissions must be < 200 words with < 5 references. Reference 1 must be the article on which you are commenting.
- Submissions should not have more than 5 authors. (Exception: original author replies can include all original authors of the article)
- Submit only on articles published within 6 months of issue date.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- Submitted comments are subject to editing and editor review prior to posting.
You May Also be Interested in
Dr. Sevil Yaşar and Dr. Behnam Sabayan
► Watch
Related Articles
Topics Discussed
Alert Me
Recommended articles
-
Article
Temporal discrimination in patients with dystonia and tremor and patients with essential tremorMichele Tinazzi, Alfonso Fasano, Alessandro Di Matteo et al.Neurology, December 12, 2012 -
Views & Reviews
Is tremor in dystonia a phenotypic feature of dystonia?Giovanni Defazio, Antonella Conte, Angelo F. Gigante et al.Neurology, February 06, 2015 -
Editorial
Sensory tricksMore than a gesture in untwisting dystonia?Timothy J. Counihan, Davide Martino et al.Neurology, January 14, 2020 -
Views & Reviews
Laryngeal DystoniaMultidisciplinary Update on Terminology, Pathophysiology, and Research PrioritiesKristina Simonyan, Julie Barkmeier-Kraemer, Andrew Blitzer et al.Neurology, April 15, 2021