This narrative review explains how transcranial magnetic stimulation (TMS) is being used to better understand Parkinson’s disease and related parkinsonian syndromes, both as a research tool and as a possible treatment aid. Across studies, the clearest pattern in Parkinson’s disease is reduced cortical inhibition, disrupted sensorimotor integration, and impaired brain plasticity. These changes show up in measures such as reduced short-interval intracortical inhibition, shortened cortical silent period, reduced short-latency afferent inhibition, and abnormal responses to plasticity protocols like paired associative stimulation and theta burst stimulation. The authors argue that these findings help link clinical symptoms—such as bradykinesia, freezing of gait, cognitive decline, hallucinations, and REM sleep behavior disorder—to underlying dysfunction in GABAergic, cholinergic, glutamatergic, and basal ganglia–thalamo–cortical networks. In that sense, TMS may eventually help stratify patients by phenotype, disease stage, or risk of complications, especially because some measures appear tied to cognition, gait, hallucinations, or medication response.
The review also finds that repetitive TMS approaches, especially high-frequency rTMS over motor cortex or dorsolateral prefrontal cortex and some theta burst protocols, show modest but promising benefits for motor symptoms, gait, depression, cognition, sleep problems, and dyskinesia. The biggest barriers to clinical use are small study sizes, mixed stimulation methods, inconsistent ON/OFF medication status, variable targets, and lack of standardized protocols. The authors conclude that TMS is not yet ready as a first-line clinical treatment or fully established biomarker. However, it has strong translational potential. That may be especially true if future research uses larger, better-controlled studies and combines TMS with tools such as MRI, EEG, and gait sensors. Together, these approaches could help build more precise, phenotype-driven treatment strategies for Parkinson’s disease, atypical parkinsonism, and some secondary parkinsonian disorders.
Reference: Cantone M, Pennisi M, Bella R, et al. Transcranial Magnetic Stimulation in Parkinson’s Disease and Parkinsonian Syndromes: A Narrative Expert Review. Life (Basel). 2026;16(2):233. doi: 10.3390/life16020233.
