Resting-state alpha reactivity is reduced in Parkinson disease and associated with gait variability

Ellen Lirani-Silva, Layla C. S. Silva, Diego Orcioli-Silva, Victor S Beretta, Lucas Gabriel Souza Franca, Daniel Boari Coelho, Rodrigo Vitorio

Research output: Working paperPreprint

Abstract

Background: The extent to which the cholinergic system contributes to gait impairments in Parkinson disease (PD) remains unclear. Electroencephalography (EEG) alpha reactivity, which refers to change in alpha power over occipital electrodes upon opening the eyes, has been suggested as a marker of cholinergic function. We compared alpha reactivity between people with PD and healthy individuals and explored its potential association with gait measures.
Methods: Eyes-closed and eyes-open resting-state EEG data were recorded from 20 people with idiopathic PD and 19 healthy individuals with a 64-channel EEG system. Alpha reactivity was calculated as the relative change in alpha power (8-13 Hz) over occipital electrodes from eyes-closed to eyes-open. Gait spatiotemporal measures were obtained with an electronic walkway. Results: Alpha reactivity was reduced in people with PD compared to healthy individuals (U = 105, p = 0.017); the rank-biserial correlation of 0.447 indicated a moderate effect size. When controlling for global cognition (Mini Mental State Examination), the group difference in alpha reactivity was no longer significant. Alpha reactivity associated with measures of gait variability only (rho = -0.437 to -0.532).
Conclusions: Reduced alpha reactivity in PD is driven by levels of global cognition and suggests impaired cholinergic function in PD. Reduced alpha reactivity was associated with greater gait variability, indicating a role of the cholinergic system in the mechanisms underlying gait variability. Therefore, the cholinergic system may represent a target for treatments aiming to reduce gait variability and alpha reactivity should be further explored as an endpoint for clinical trials.
Competing Interest Statement
The authors have declared no competing interest.
Original languageEnglish
Place of Publication Cold Spring Harbor, US
PublisherCold Spring Harbor Laboratory Press
Number of pages25
DOIs
Publication statusSubmitted - 29 Nov 2024

Keywords

  • locomotion
  • balance
  • acetylcholine

Cite this