SynthesisMovement disorders : official journal of the Movement Disorder Society2026
Speech and Deep Brain Stimulation in Parkinson's Disease, Essential Tremor, and Dystonia: A Systematic Review and Meta-analysis.
Synthesis in Movement disorders : official journal of the Movement Disorder Society, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
1 citing paper in PubMed.
- Tremor relief after gamma knife thalamotomy for Parkinson's disease.Neurosurgical review · 2026Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
16 authors.
Funding
Abstract
Deep brain stimulation (DBS) effectively treats motor symptoms in movement disorders but often compromises speech through incompletely defined mechanisms. We conducted a PROSPERO-registered systematic review and meta-analysis of publications through August 2024 (CRD42024527738). Among 2726 screened records, we included 184 studies: 131 in Parkinson's disease (PD), 32 in essential tremor (ET), and 21 in dystonia, assessing perceptual, acoustic, and patient-reported speech outcomes. Meta-analyses showed that subthalamic nucleus DBS in PD resulted in poorer speech intelligibility compared with best medical treatment (effect size -0.24; 95% confidence interval: -0.46 to -0.03; P = 0.027), with state-dependent decline under active stimulation on longitudinal analysis (Unified Parkinson's Disease Rating Scale Part III item 18 monthly change: medication on +0.016, P < 0.001; medication off +0.002, P = 0.50). In ET, DBS consistently suppressed vocal tremor but increased the risk of dysarthria, particularly with bilateral stimulation. Dystonia outcomes showed greater heterogeneity. Across disorders, sustained phonation measures improved, whereas connected speech performance worsened, indicating selective vulnerability of complex motor tasks. Neuroanatomical mapping identified two nonexclusive mechanisms: current spread to corticobulbar fibers producing spastic speech features and to the cerebellothalamocortical pathway producing ataxic features. Hypokinetic and stuttering-like phenotypes also occurred but likely reflect network-level interactions rather than tract-specific spread. These tract-mediated and network-level alterations appear to interact with hemispheric lateralization, medication state, and longer-term plasticity to produce complex clinical phenotypes. We outline a clinical framework integrating systematic screening, phenotype identification, and targeted programming adjustments. Enhanced speech assessment, precise field mapping, and adaptive DBS paradigms may promote individualized care that optimizes speech and motor function in precision DBS therapy. © 2026 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.