Transcranial Magnetic Stimulation Treatment for Motor Symptoms in Parkinson’s Disease: A Review of Two Decades of Studies

In the last two decades, repetitive Transcranial Magnetic Stimulation (rTMS) has been increasingly employed in Parkinson’s disease (PD) to enhance and restore motor function. Different cortical regions have been investigated as treatment targets (i.e. primary motor cortex, dorsolateral prefrontal cortex and supplementary motor area) and stimulation parameters (frequency, intensity, number of pulses) showed high heterogeneity between studies. Herein we review 40 studies, both open-label and randomized controlled trials: mixed results have been yielded regarding the effectiveness of rTMS treatment for motor symptoms in PD, due to the high variability of employed protocols, sham procedures and target regions. Although overall results seem to support the notion of potential beneficial effects of rTMS in PD, further research is needed to identify the optimal treatment parameters and to evaluate the potential conjunct use of rTMS in patients with deep brain stimulation (DBS) implants.