Force control deficits in rapid eye movement behavior disorder and Parkinson's disease

Emily R Tobin; Stefan Delmas; Joongsuk J Kim; Jessica C Hubbard; Basma Yacoubi; XiangYang Lou; Michael F Presti; Allison Kraus; Richard B Berry; Michael S Jaffee; Evangelos A Christou; David E Vaillancourt

doi:10.1016/j.clinph.2025.2110763

Force control deficits in rapid eye movement behavior disorder and Parkinson's disease

Clin Neurophysiol. 2025 Aug:176:2110763. doi: 10.1016/j.clinph.2025.2110763. Epub 2025 May 25.

Authors

Affiliations

¹ Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA. Electronic address: tobine@ufl.edu.
² Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA. Electronic address: stefan.demas@colostate.edu.
³ Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA. Electronic address: joongsuk.kim@ufl.edu.
⁴ Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA. Electronic address: jessica.hubbard@ufl.edu.
⁵ Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA. Electronic address: basma@ufl.edu.
⁶ Department of Biostatistics, University of Florida, Gainesville, FL 32610, USA. Electronic address: xlou@ufl.edu.
⁷ Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Florida, Gainesville, FL 32610, USA. Electronic address: Michael.Presti@medicine.ufl.edu.
⁸ Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA. Electronic address: alk127@case.edu.
⁹ Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Florida, Gainesville, FL 32610, USA. Electronic address: richard.berry@medicine.ufl.edu.
¹⁰ Department of Neurology, University of Florida, Gainesville, FL 32610, USA. Electronic address: michael.jaffee@neurology.ufl.edu.
¹¹ Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; Department of Neurology, University of Florida, Gainesville, FL 32610, USA. Electronic address: eachristou@ufl.edu.
¹² Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; Department of Biomedical Engineering, University of Florida, Gainesville, FL 32610, USA; Department of Neurology, University of Florida, Gainesville, FL 32610, USA. Electronic address: vcourt@ufl.edu.

PMID: 40472441
PMCID: PMC12320221 (available on 2026-05-25)
DOI: 10.1016/j.clinph.2025.2110763

Abstract

Objective: This study aimed to determine if there are deficits in force variability, force increase, force decrease and force errors in rapid eye movement behavior disorder (RBD) using established force control paradigms.

Methods: A cohort of 27 controls, 37 RBD and 37 early-stage Parkinson's disease (PD) were investigated. Individuals completed constant force and ballistic force control for the finger and ankle.

Results: There was greater force variability in RBD compared with controls and PD during the constant force tasks (p < 0.05). Additionally, we split the RBD group into those with mild and moderate motor impairments and found both groups had higher force variability compared with controls (p < 0.05). PD were slower at increasing and decreasing force (p < 0.05) and this was not observed in the RBD group.

Conclusion: These findings provide new evidence that force variability may be one of the earliest markers of motor dysfunction in RBD before a subsequent diagnosis of neurological disease.

Significance: These findings provide new and important insights into the motor physiological changes in force control in RBD and PD, which may inform future biomarker studies.

Keywords: Force control; Force variability, ballistic task; Parkinson’s disease; REM sleep behavior disorder.

MeSH terms

Aged
Female
Humans
Male
Middle Aged
Parkinson Disease* / diagnosis
Parkinson Disease* / physiopathology
Psychomotor Performance* / physiology
REM Sleep Behavior Disorder* / diagnosis
REM Sleep Behavior Disorder* / physiopathology

Abstract

MeSH terms

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