How deep brain stimulation affects learning and producing speech in Parkinson's disease and essential tremor

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

The project compares two groups—people with Parkinson's disease implanted with STN-targeted DBS and people with essential tremor implanted with VIM-targeted DBS—to determine how subcortical circuits contribute to speech sequencing. Participants perform phoneme and multisyllabic sequence learning and repetition tasks while stimulation is systematically turned on and off in controlled sessions. Many participants implanted with the Medtronic Percept device will have deep brain activity recorded during tasks to link stimulation state with neural signals and behavior. The design separates effects on learning new sequences from effects on producing previously learned sequences.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Native speakers of American English
* Adults at least 18 years of age
* A clinically established diagnosis of Parkinson's disease or essential tremor
* Able to provide informed consent in the judgment of the investigator
* Treated with deep brain stimulation of the subthalamic nucleus (Parkinson's disease) or ventral intermediate nucleus of the thalamus (essential tremor)
* Stable Parkinson's disease or essential tremor medication regimen for at least one month
* Stable DBS program settings for at least one month
* Nominal DBS system function, including normal impedances at therapeutic DBS contacts, and adequate battery life or adequate IPG charging status for therapy
* For DBS sensing, implanted with Medtronic Percept PC or Percept RC implantable pulse generator
* Corrected vision adequate to easily read text presented during speech motor task

Exclusion Criteria:

* Cognitive impairment (Montreal Cognitive Assessment (MoCA; Nesreddine et al., 2005) score \< 25) or active psychotic or behavioral symptoms that would, in the judgment of the investigator, preclude proper participation in the study
* Hearing impairment that interferes with accurate perception of the speech motor learning stimulus (25dB hearing level threshold at 500, 1k, 2k, and 4kHz frequencies)
* Language impairment (aphasia) or speech articulation impairment (dysarthria) that precludes performance of the speech motor learning task
* Neurological disorder that interferes with speech motor learning
* Inability to tolerate symptoms when DBS is off
* Orthodontia or atypical oral structure (e.g., cleft palate) that interferes with speech
* Pregnancy
* For participants in the sub-syllabic sequence learning study (Study C.2.1), experience with the following languages: Hebrew, Polish, Lithuanian, Romanian, Georgian, Tepehua, Hungarian, and Pima

Where it's running

• Boston University
  Boston, Massachusetts, United States Recruiting
• Massachusetts General Hospital
  Boston, Massachusetts, United States Recruiting

Study contacts

• Principal investigator: Frank H Guenther, Ph.D. — Boston University
• Study coordinator: Frank H Guenther, Ph.D.
• Email: guenther@bu.edu
• Phone: 617-353-5765

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

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• Closed-loop TMS to reduce tremor

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• Encora X1 in Daily Life for Essential Tremor

  This real-world study tests how the Encora X1 wrist device affects day-to-day activities for adults with essential tremor over three years.

  Recruiting Encora, Inc. · Boston, Massachusetts · NCT07911488

• Automated language analysis to help diagnose neurodegenerative diseases

  A multilingual AI-powered language test is being tried to see if speech and language patterns can help differentiate Alzheimer’s, frontotemporal dementia, Lewy body dementia, and Parkinson’s from healthy aging.

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• Brain alpha-synuclein PET imaging in Parkinson's patients and healthy seniors

  This open-label study tests a radioactive tracer called [18F]MK-0947 to see how it behaves in the brains of people with Parkinson's disease compared with healthy elderly volunteers.

  Recruiting Phase 1 XingImaging, LLC · New Haven, Connecticut · NCT07880379

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.