Objective: To compare keyboard tapping performance in people with iRBD with controls.
Background: The Distal Finger Tapping (DFT)1 test and BRadykineisa Akinesia Incoordination test (BRAIN)2 test are web-based keyboard tapping tests which have been validated to evaluate upper-limb motor dysfunction in Parkinson’s disease (PD). They are part of the online assessment in the PREDICT-PD study. Separately, slowing in alternate finger tapping speed was found in patients with isolated REM Sleep Behaviour Disorder (iRBD) up to 10 years before parkinsonism diagnosis3.
Method: This was a cross-sectional study of 58 participants (29 video polysomnography confirmed iRBD and 29 age and sex frequency matched controls). The DFT test consists of a 20-second single key tapping test. The BRAIN test is a 30-second alternating finger tapping test. Kinetic parameters of both tests include kinesia score (KS-BRAIN/DFT, key taps over 20s/30s), akinesia time (AT-BRAIN/DFT, mean dwell-time on each key) and incoordination score (IS-BRAIN/DFT, variance of traveling time between key taps).
Results: Participants with iRBD performed the BRAIN tests more slowly than controls (KS-BRAIN: 49.8 taps (SD, 16.3) vs 60.9 taps (SD 10), p=0.002) and the DFT with greater incoordination (IS-DFT: 4841.8 (SD,7072.5) vs 1374.8 (SD 1618.9), p=0.008). All parameters discriminated effectively between groups, with the combination of KS-BRAIN and IS-DFT performing best, yielding 71.4% sensitivity and 72.4% specificity with an area under the receiver operating discrimination (AUC) of 0.76 (95%CI 0.62-0.88).
Conclusion: There are detectable differences in motor performance between participants with iRBD and controls. Keyboard tapping was found to be slow and erratic in people with iRBD, which suggests that speed and incoordination might be potential motor prodromes of neurodegeneration.
References: 1. Akram, N., Li, H., Ben-Joseph, A. et al. Developing and assessing a new web-based tapping test for measuring distal movement in Parkinson’s disease: a Distal Finger Tapping test. Sci Rep 12, 386 (2022). https://doi.org/10.1038/s41598-021-03563-7.
2. Noyce AJ, Nagy A, Acharya S, Hadavi S, Bestwick JP, Fearnley J, Lees AJ, Giovannoni G. Bradykinesia-akinesia incoordination test: validating an online keyboard test of upper limb function. PLoS One. 2014 Apr 29;9(4):e96260. doi: 10.1371/journal.pone.0096260. Erratum in: PLoS One. 2014;9(8):e105488. PMID: 24781810; PMCID: PMC4004565.
3. Seyed-Mohammad Fereshtehnejad, Chun Yao, Amelie Pelletier, Jacques Y Montplaisir, Jean-François Gagnon, Ronald B Postuma, Evolution of prodromal Parkinson’s disease and dementia with Lewy bodies: a prospective study, Brain, Volume 142, Issue 7, July 2019, Pages 2051–2067, https://doi.org/10.1093/brain/awz111.
To cite this abstract in AMA style:
C. Simonet, L. Perez-Carbonell, H. Chohan, N. Akram, H. Li, A. Gill, J. Bestwick, A. Lees, A. Schrag, A. Noyce. Remote keyboard tapping: potential signatures of early motor dysfunction in isolated REM sleep behaviour disorder [abstract]. Mov Disord. 2022; 37 (suppl 2). https://www.mdsabstracts.org/abstract/remote-keyboard-tapping-potential-signatures-of-early-motor-dysfunction-in-isolated-rem-sleep-behaviour-disorder/. Accessed May 12, 2025.« Back to 2022 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/remote-keyboard-tapping-potential-signatures-of-early-motor-dysfunction-in-isolated-rem-sleep-behaviour-disorder/