The effects of transcranial direct current stimulation on gait in patients with Parkinson’s disease: a systematic review

Abstract

Background Gait problems are an important symptom in Parkinson’s disease (PD), a progressive neurodegenerative disease. Transcranial direct current stimulation (tDCS) is a neuromodulatory intervention that can modulate cortical excitability of the gait-related regions. Despite an increasing number of gait-related tDCS studies in PD, the efficacy of this technique for improving gait has not been systematically investigated yet. Here, we aimed to systematically explore the effects of tDCS on gait in PD, based on available experimental studies. Methods Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach, PubMed, Web of Science, Scopus, and PEDro databases were searched for randomized clinical trials assessing the effect of tDCS on gait in patients with PD. Results Eighteen studies were included in this systematic review. Overall, tDCS targeting the motor cortex and supplementary motor area bilaterally seems to be promising for gait rehabilitation in PD. Studies of tDCS targeting the dorosolateral prefrontal cortex or cerebellum showed more heterogeneous results. More studies are needed to systematically compare the efficacy of different tDCS protocols, including protocols applying tDCS alone and/or in combination with conventional gait rehabilitation treatment in PD. Conclusions tDCS is a promising intervention approach to improving gait in PD. Anodal tDCS over the motor areas has shown a positive effect on gait, but stimulation of other areas is less promising. However, the heterogeneities of methods and results have made it difficult to draw firm conclusions. Therefore, systematic explorations of tDCS protocols are required to optimize the efficacy.

Anodal Transcranial Direct Current Stimulation Could Modulate Cortical Excitability and the Central Cholinergic System in Akinetic Rigid-Type Parkinson's Disease: Pilot Study

“…On the other hand, we did not discover the anodal tDCS effect for the axial symptoms in PD. There have been several studies showing the efficacy of tDCS on axial symptoms in PD ( 13 , 18 , 64 , 65 ). Pol et al suggested that anodal tDCS over the motor areas has revealed positive effect on gait in a meta-analysis ( 18 ).…”

“…There have been several studies showing the efficacy of tDCS on axial symptoms in PD ( 13 , 18 , 64 , 65 ). Pol et al suggested that anodal tDCS over the motor areas has revealed positive effect on gait in a meta-analysis ( 18 ). However, there have been contradictory results that anodal tDCS on the motor cortex did not show efficacy on gait.…”

“…Many studies have shown the beneficial effects of tDCS on various symptoms in PD ( 9 , 13 – 19 ). Ishikuro et al reported that anodal tDCS in the frontal polar area improved the motor and executive function of patients with PD, and some meta-analytic studies have indicated that tDCS could have a positive effect on locomotive and gait function in PD, despite insufficient sample power to draw firm conclusions in most studies ( 15 , 18 , 20 ).…”

Effectiveness of a 12-Week Multi-Component Training Program with and without Transcranial Direct-Current Stimulation (tDCS) on Balance to Prevent Falls in Community-Dwelling Older Adults: A Study Protocol

“…The tDCS can stimulate neuroplasticity becase it modulates changes in neuronal membrane potential and produces an increase in cortical excitability [ 28 ]. Some works indicate that tDCS facilitates long-term potentiation by depolarizing the membrane potential, resulting in better motor learning, leading to possible gait performance improvements [ 33 , 34 , 35 , 36 ] and fall prevention. Halo Sport, a few years ago, marketed a device to improve physical performance based on tDCS [ 37 ].…”

Transcranial ultrasound stimulation applied in ischemic stroke rehabilitation: A review

“…TMS modulates neuronal excitability by generating a magnetic field that induces neuronal depolarization (Antczak et al, 2021), and it can also cause vascular cognitive impairment, which may lead to dementia (Cantone et al, 2020;. tDCS and tACS can modulate cortical excitability by hyperpolarization or depolarization neuronal resting membrane potentials (Pol et al, 2021). However, Airan reported that the absorption and scattering of magnetic and electrical signals within the brain limits the spatial resolution and penetration depth of these techniques, which further hinders their application for the treatment of stroke (Airan, 2017).…”