Neurofeedback-Linked Suppression of Cortical β Bursts Speeds Up Movement Initiation in Healthy Motor Control: A Double-Blind Sham-Controlled Study

Abstract

Abnormally increased beta bursts in cortical-basal ganglia-thalamic circuits are associated with rigidity and bradykinesia in patients with Parkinson's disease. Increased beta bursts detected in the motor cortex have also been associated with longer reaction times in healthy participants. Here we further hypothesize that suppressing beta bursts through neurofeedback training can improve motor performance in healthy subjects. We conducted a double-blind sham-controlled study on 20 human volunteers (10 females) using a sequential neurofeedback-behaviour task with the neurofeedback reflecting the occurrence of beta bursts over sensorimotor cortex quantified in real-time. The results show that neurofeedback training helps healthy participants learn to volitionally suppress beta bursts in the sensorimotor cortex, with training being accompanied by reduced reaction time in subsequent cued movements. These changes were only significant in the real feedback group but not in the sham group, confirming the effect of neurofeedback training over simple motor imagery. In addition, reaction times correlated with the rate and accumulated duration of beta bursts in the contralateral motor cortex before the Go cue, but not with averaged beta power. The reduced reaction times induced by neurofeedback training positively correlated with reduced beta bursts across all tested hemispheres. These results strengthen the link between the occurrence of beta bursts in the sensorimotor cortex before the Go cue and slowed movement initiation in healthy motor control. The results also highlight the potential benefit of neurofeedback training in facilitating voluntary suppression of beta bursts in order to speed up movement initiation. Significance This double-blind sham-controlled study suggested that neurofeedback training can facilitate volitional suppression of beta bursts in sensorimotor cortex in healthy motor control better 3 than sham feedback. The training was accompanied by reduced reaction time in subsequent cued movements, and the reduced reaction time positively correlated with the level of reduction in cortical beta bursts before the Go cue, but not with average beta power. These results provide further evidence of a causal link between sensorimotor beta bursts and movement initiation and suggest that neurofeedback training could potentially be used to train participants to speed up movement initiation.

Subthalamic beta-targeted neurofeedback speeds up movement initiation but increases tremor in Parkinsonian patients

“…When the EEG beta band and alpha band activities, and the experimental condition were considered as the only predictors in the model, the EEG beta band activity also contributed to the prediction of reaction time (k = 0.0067 ± 0.0024, p = 0.0058, Model 8, Table II), consistent with previous findings in young healthy participants (He et al 2020). However, when EEG beta, STN beta and STN gamma were considered together in one model, only STN beta and STN gamma significantly contributed to the prediction of reaction time (Model 9, Table II).…”

“…It should be acknowledged that proper sham control would be required to determine whether observed behavioural and electrophysiological alterations were due to veritable neurofeedback or mediated by other mental strategies (Thibault et al 2015;. Our recent study (He et al 2020)…”

“…Similar experimental designs have helped to shed light on the relationship between neural activity and behavior ( McFarland et al, 2015 ; Khanna and Carmena, 2017 ). In a recent study, we showed that healthy young participants can indeed suppress cortical beta measured using electroencephalogram (EEG) with veritable neurofeedback better than sham feedback ( He et al, 2020 ). In the paradigm of the current study, a cued finger pinch movement followed a neurofeedback phase during which the position of a visual cue was controlled by suppressing high amplitude beta bursts in activities measured by DBS electrodes implanted in the STN.…”

“…Thus, considering that externalised patients provide a rare opportunity to understand the response of STN activity to interventions, we did not include a sham condition but only used veritable neurofeedback.Here we argue that veritable neurofeedback may help patients to develop an efficient mental strategy to modulate targeted pathological activities in a short period of time. Our recent study(He et al 2020) suggested that suppression of sensorimotor cortex beta bursts facilitated by neurofeedback training could help improve movement initiation in healthy subjects. The current study suggests that suppression of STN beta bursts facilitated by neurofeedback training also led to a trend of reduced beta over the motor cortex, and reduced beta band coherence between the STN and ipsilateral motor cortex.…”

Program of Seven 45-min Dry Immersion Sessions Improves Choice Reaction Time in Parkinson’s Disease

“…By this fact, it seems that attention and RT are improved when α-waves on EEG become more powerful. Indeed, suppression of β-wave bursts on EEG helped in decreasing RT ( He et al, 2020 ). During the 5-day DI experiment, α-waves in young subjects were most powerful on the fifth day, supposedly due to reduced sensory flow to the brain cortex from the sole supportive skin zone ( Lazarev et al, 2018 ).…”