Repetitive Transcranial Magnetic Stimulation Does Not Improve the Sequence Effect in Freezing of Gait

Abstract

Introduction. The sequence effect (SE) is a reason contributing to freezing of gait (FOG) in Parkinson’s disease (PD) patients. There is no effective treatment for the SE. The objective of the current study is to investigate the effect of repetitive transcranial magnetic stimulation (rTMS) on the SE in PD patients with FOG. Methods. 28 PD patients with FOG received either real or sham 10-Hz rTMS over the supplementary motor area (SMA). The effects of rTMS on the SE, FOG, and some gait parameters were evaluated. Results. rTMS did not improve the SE. Real rTMS had beneficial effects on FOG and some gait parameters, and this effect lasted for at least four weeks. Conclusions. High-frequency rTMS over the SMA cannot alleviate the SE in PD patients with FOG. rTMS has a long-lasting beneficial effect on FOG; however, this effect is not achieved by improving the SE but may be through improving some other gait parameters.

Transverse Strips Instead of Wearable Laser Lights Alleviate the Sequence Effect Toward a Destination in Parkinson's Disease Patients With Freezing of Gait

“…When calculating the regression slopes for the section of walking trials toward a destination, step length data for the six consecutive footsteps ahead of the last stride was used to avoid the influence of sharp deceleration ( Figure 1C). After being numbered in sequence, the step length was plotted against step number in each walking trial, according to previous studies (11,14,24). The regression slopes (β), representing the sequence effect toward a destination for each individual walk, were averaged to formulate group mean average slopes, which were compiled for each condition (no cue, laser lights and transverse strips).…”

The Effects of Intensive Neurorehabilitation on Sequence Effect in Parkinson's Disease Patients With and Without Freezing of Gait

“…If the basal ganglia/SMA system appears to be crucial in the SE generation, it is difficult to hypothesize that our rehabilitative interventions might exert a positive modulation of SE trough this pathway. This idea is corroborated by the lack of efficacy on SE of either L-dopa administration, which mainly acts at the basal ganglia level, or rTMS direct modulation of SMA (18,(26)(27)(28)42).…”

“…As previously described, the last stride was excluded to avoid interference of sharp deceleration before gait ending. The length of the last six steps (y) ahead of the final stride was then plotted against step number (x), and the linear regression slope (β) was calculated as a measure of dSE (16)(17)(18)26). In addition, the intercept (I) of the regression curve was used as an indirect measure of gait hypokinesia (17,18).…”

“…SE may be acutely modulated by several rehabilitative strategies such as split-belt treadmill ( 25 ) and reinforcement of visual cues ( 16 ), while repetitive transcranial magnetic stimulation (rTMS), antiparkinsonian dopaminergic drug administration, and attention strategies were found not to influence the SE ( 18 , 26 , 27 ). Kang et al demonstrated a positive effect of exercise training on SE evaluated at upper limb in de novo PD patients ( 28 ), while the evidence on the role of neurorehabilitation on gait SE improvement and retention is extremely scarce ( 16 , 28 ).…”

Cortical visuomotor interactions in Freezing of Gait: A TMS approach

“…Its applications to FoG were initially limited to studies of hand motor learning after auditory cues [7], and of short-latency afferent inhibition (SAI) recording from a small hand muscle (FDI), which was found to be normal [27]. Repetitive TMS targeting M1, the supplementary motor area or the prefrontal cortex, was subsequently explored as a treatment approach to FoG with somewhat controversial results [8,20,23].…”