We appreciate the interest of Maciel and colleagues 1 in our recent publication, and we are pleased that the authors confirm our observation concerning temporary suppression of chorea. 2
The authors present a case of a 40‐year‐old gentleman with a diagnosis of chorea‐acanthocytosis, in which, differently from what is normally observed, choreic movements subsided when performing cognitive tasks involving motor skills (i.e., unlocking a mobile). 1 Similar to our cases, no premonitory urge was observed. 1 , 2
However, unlike our cases, Maciel and colleagues did not observe a temporary suppression of involuntary movements on command. 1 This observation is of particular interest since it suggests that chorea may be controlled by two different mechanisms, voluntary inhibition and attention, which do not necessarily occur together. This also holds true for tic control. In fact, Misirlisoy and colleagues demonstrated that in tics the distraction provided by attending specifically to finger actions during motor tasks seemed to determine a significant reduction of involuntary movements. 3 In particular, the authors observed that patients may be able to obtain by attentional focus a decrease in involuntary movements as successful as those with active tic inhibition. 3 In addition, they proved that tic inhibition was more beneficial when focusing on voluntary compared to involuntary actions. 3 The authors suggested that mechanism of attentional modulation is likely to be different to voluntary inhibition, since they probably act at a different tic generator stage. 3 Based on clinical evidence, we might assume that similar mechanisms occur in chorea, but confirmatory experimental data are needed.
In view of this novel observation, it is relevant to recognize the temporary suppression of chorea in clinical practice.
We believe this case represents an additional step forward towards a new definition of chorea.
Author Roles
Author Roles: 1) Research project: A. Conception, B. Organization, C. Execution; 2) Statistical Analysis: A. Design, B. Execution, C. Review and Critique; 3) Manuscript Preparation: A. Writing of the first draft, B. Review and Critique.
RB: 1B, 1C; 3A
AL: 1B, 1C; 3A
KPB: 1A, 3B
Disclosures
Ethical Compliance Statement
We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines. The patients have given written and informed consent for online publication of their videos. The authors confirm that the approval of an institutional review board was not required for this work.
Funding Sources and Conflicts of Interest
No specific funding was received for this work. The authors declare that there are no conflicts of interest relevant to this work.
Financial Disclosures for the Previous 12 months
KPB holds research grants from NIHR RfPB, MRC Wellcome Strategic grant (Ref. no.: WT089698) and PD UK (Ref. no.: G‐1009) and has received honoraria/financial support to speak/attend meetings from GSK, Boehringer‐Ingelheim, Ipsen, Merz, Sun Pharma, Allergan, Teva, Lundbeck and Orion pharmaceutical companies. KPB receives royalties from Oxford University press and a stipend for MDCP editorship. All the other authors have no disclosures.
References
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