Parkinson's Disease (PD)NCT07455760
Investigating Subcortical Contributions to Speech Sequencing in Deep Brain Stimulator Recipients
A study testing Phoneme sequence learning, Cessation and re-enabling of stimulation of the STN and Cessation and re-enabling of stimulation of the VIM thalamic nucleus in people with Parkinson's Disease (PD) and Essential Tremor, run by Boston University Charles River Campus at 2 sites in United States.
Trial summary
This study will examine how two important brain circuits - one involving the subthalamic nucleus (STN) and one involving the ventral intermediate nucleus of the thalamus (VIM) - contribute to learning and producing speech sequences. Participants will include two groups: 1. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Parkinson's Disease (PD), Essential Tremor
- What is being tested?
- Phoneme sequence learning, Cessation and re-enabling of stimulation of the STN and Cessation and re-enabling of stimulation of the VIM thalamic nucleus
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 80 participants
- Where
- 2 sitesUnited States
- Study dates
- 18 Feb 2026to Aug 2030
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Show all 10Show fewer
- 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
Who cannot join
- 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
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
United States2 sites, 2 recruiting
- Recruiting
Boston University
Boston, Massachusetts, 02215
Frank H Guenther, Ph.D., 617-353-5765, guenther@bu.edu
Barbara G Holland, MA, bobbieh@bu.edu
- Recruiting
Massachusetts General Hospital
Boston, Massachusetts, 02215
Todd Herrington, MD, PHD, 6177265532, therrington@mgh.harvard.edu
Zeyang Yu, PHD
About this study
This study will examine how two important brain circuits - one involving the subthalamic nucleus (STN) and one involving the ventral intermediate nucleus of the thalamus (VIM) - contribute to learning and producing speech sequences. Participants will include two groups: 1. individuals with Parkinson's disease who have deep brain stimulation (DBS) devices targeting the STN and 2. individuals with essential tremor who have DBS devices targeting the VIM.
Participants will complete speech tasks involving the learning and repetition of novel sound sequences. During some parts of the study, DBS stimulation will be temporarily turned on or off in a controlled research setting. This will allow researchers to examine how stimulation affects both the learning of new speech sequences and the production of previously learned sequences. All STN participants and most VIM participants will also be equipped with a cutting-edge DBS system, the Percept PC, which will enable the recording of deep brain activity during the tasks.
The results of this study will improve our understanding of how different brain circuits support speech learning and production. In particular, this study will help to differentiate the roles of the STN and VIM in learning the ordering of speech sounds within a syllable from learning of speech sequences containing multiple syllables. This knowledge may help guide future approaches to optimizing DBS settings to improve both movement and speech outcomes in individuals with neurological disorders, as well as provide greater general insight into how these brain structures contribute to speech production and learning.
- Conditions
- Parkinson's Disease (PD), Essential Tremor
- Being tested
- Phoneme sequence learning, Cessation and re-enabling of stimulation of the STN, Cessation and re-enabling of stimulation of the VIM thalamic nucleus, Multisyllabic sequence learning
- Keywords
- Deep Brain Stimulation, Parkinson's Disease, Essential Tremor, Speech Disorders, Neurocomputational Modeling, Stuttering
- Medical subject headings
- Parkinson Disease, Essential Tremor, Speech Disorders, Stuttering
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Phoneme sequence learningBehavioural
Approximately half of subjects enrolled in the study will participate in this intervention.
Subjects will read aloud monosyllabic sequences that are presented orthographically on a screen. Each sequence is formed by a non-native consonant cluster followed by a vowel and final consonant (CCVC). Speech trials will be grouped into blocks. After a Familiarization block, subjects will produce a set of twelve CCVCs in a Pretest block. Subjects will then repeatedly produce two of those CCVCs in one Training block, and two other CCVCs in a subsequent Training block. Following training, subjects will produce all four trained CCVCs and four additional novel CCVCs in each of two Test blocks. Washout blocks, during which no speech task trials are completed, will follow the Pretest, Training, and first Test block to allow subjects to rest and to complete standardized testing.
Cessation and re-enabling of stimulation of the STNOther
20 adults with Parkinson's disease (PD) who have deep brain stimulator (DBS) implants in the subthalamic nucleus (STN). Stimulation of the STN will be intermittently turned off while subjects complete speech sequence learning tasks. After no more than 35 minutes, stimulation will be re-enabled with normal clinical parameters for each participant.
Cessation and re-enabling of stimulation of the VIM thalamic nucleusOther
20 adults with essential tremor who have deep brain stimulator (DBS) implants in the ventral intermediate nucleus (VIM) of the thalamus will participate in this intervention. Stimulation of the VIM will be intermittently turned off (DBS OFF state) while subjects complete speech sequence learning tasks. After no more than 35 minutes, stimulation will be re-enabled with normal clinical parameters for each participant.
Multisyllabic sequence learningBehavioural
Approximately half of subjects enrolled in the study will participate in this intervention.
Subjects will read aloud sequences that are presented orthographically on a screen. Speech trials will be grouped into blocks. After a Familiarization block, subjects will produce 2- and 7-syllable sequences in an Assessment block to determine the appropriate length sequence for the remainder of the intervention. Subjects will produce a set of eight sequences in a Pretest block. Subjects will then repeatedly produce two of those sequences in one Training block and two other sequences in a subsequent Training block. Following training, subjects will produce all four trained sequences and two additional novel sequences in each of two Test blocks. Washout blocks, during which no speech task trials are completed, will follow the Pretest, Training, and first Test Block to allow subjects to rest and to complete standardized testing.
| Study group | Role | What they receive |
|---|---|---|
| Subthalamic nucleus with subsyllabic learning arm | Experimental | Arm 1: subjects with implanted STN deep brain stimulators will undergo learning tasks involving non-English sound sequences while their stimulators are turned on and off Receives: Behavioral: Phoneme sequence learning; Other: Cessation and re-enabling of stimulation of the STN |
| Subthalamic nucleus with multisyllabic learning arm | Experimental | Arm 2: subjects with implanted STN deep brain stimulators will undergo learning tasks involving syllable sequences while their stimulators are turned on and off Receives: Other: Cessation and re-enabling of stimulation of the STN; Behavioral: Multisyllabic sequence learning |
| Ventral intermediate thalamus with subsyllabic learning arm | Experimental | Arm 3: subjects with implanted VIM deep brain stimulators will undergo learning tasks involving non-English sound sequences while their stimulators are turned on and off Receives: Behavioral: Phoneme sequence learning; Other: Cessation and re-enabling of stimulation of the VIM thalamic nucleus |
| Ventral intermediate thalamus with multisyllabic learning arm | Experimental | Arm 4: subjects with implanted VIM deep brain stimulators will undergo learning tasks involving syllable sequences while their stimulators are turned on and off Receives: Other: Cessation and re-enabling of stimulation of the VIM thalamic nucleus; Behavioral: Multisyllabic sequence learning |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in speech sequencing accuracy
Investigators will evaluate recordings of speech productions to identify errors. This will be used to compare sequence accuracy before and after practice of novel sequences with DBS in the ON and OFF states.
Measured: Day 1
Speech production duration
Investigators will inspect recordings of speech productions to identify production duration. This will be used to test hypotheses regarding differences in sequence duration before and after practice of novel sequences and with DBS in the ON and OFF states.
Measured: Day 1
Beta power during speech production
Investigators will extract beta band (12-20 Hz) power from neural recordings taken while subjects practice and rehearse novel speech sequences. This will be used to test hypotheses regarding differences in beta power before and after practice of novel sequences and with DBS in the ON and OFF states.
Measured: Day 1
Secondary outcomes (4)
Cognitive Assessment
The Montreal Cognitive Assessment (MoCa) test will be administered to all participants. Scores will be used to determine study eligibility and to identify correlations between cognitive capacity and other outcome measures. Score range: 0-30, higher score indicates higher cognitive performance.
Measured: Baseline
Forward Digit Span
The forward digit span subtest of the Comprehensive Test of Phonological Awareness, 2nd Edition will be administered to all participants. Scores will be used to identify correlations between working memory capacity and other outcome measures.
Measured: Baseline
Essential tremor severity
Participants with essential tremor will complete The Essential Tremor Rating and Assessment Scale (TETRAS) in both the DBS ON and OFF states to assess disease severity and to identify correlations between severity and other outcome measures. Score range: 0-64, lower score indicates less severe tremor.
Measured: Day 1
Parkinson's disease severity
Part III (motor examination) of the Movement Disorder Society-sponsored revision of the Unified Parkinson's disease Ratings Scale (UPDRS part 3) will be administered to participants with Parkinson's disease in both the DBS ON and OFF states to assess disease severity and to identify correlations between severity and other outcome measures. Score range: 0-132, lower scores indicate lower motor symptom severity.
Measured: Day 1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Mar 2026
- Study start18 Feb 2026
- Primary completionAug 2030 (estimated)
- Study completionAug 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Parkinson's Disease (PD)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Boston University Charles River Campus
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute on Deafness and Other Communication Disorders (NIDCD), Massachusetts General Hospital
- Responsible party
- Principal investigator, Frank Guenther, Boston University Charles River Campus
- Investigators
- Frank H Guenther, Ph.D., Principal investigator, Boston University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07455760
- Sponsor's protocol ID
- Guenther_8238
- Other IDs
- R01DC022949
- Status last verified
- Mar 2026
- First submitted
- 3 Mar 2026
- Last updated
- 9 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: All planned analyses will be carried out by research staff who are already facilitating the study.
Study at a glance
From the registry record, last updated by the sponsor on 9 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Investigating Subcortical Contributions to Speech Sequencing in Deep Brain Stimulator Recipients
- ClinicalTrials.gov ID
- NCT07455760
- Acronym / sponsor ID
- Guenther_8238
- Conditions
- Parkinson's Disease (PD), Essential Tremor
- Keywords
- Deep Brain Stimulation, Parkinson's Disease, Essential Tremor, Speech Disorders, Neurocomputational Modeling, Stuttering
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- Boston University Charles River CampusUniversity, hospital or other
- Collaborators
- National Institute on Deafness and Other Communication Disorders (NIDCD), Massachusetts General Hospital
- Study start
- 18 Feb 2026 (actual)
- Primary completion
- Aug 2030 (estimated)
- Study completion
- Aug 2030 (estimated)
- First posted
- 6 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will examine how two important brain circuits - one involving the subthalamic nucleus (STN) and one involving the ventral intermediate nucleus of the thalamus (VIM) - contribute to learning and producing speech sequences. Participants will include two groups: 1. individuals with Parkinson's disease who have deep brain stimulation (DBS) devices targeting the STN and 2. individuals with essential tremor who have DBS devices targeting the VIM.
Participants will complete speech tasks involving the learning and repetition of novel sound sequences. During some parts of the study, DBS stimulation will be temporarily turned on or off in a controlled research setting. This will allow researchers to examine how stimulation affects both the learning of new speech sequences and the production of previously learned sequences. All STN participants and most VIM participants will also be equipped with a cutting-edge DBS system, the Percept PC, which will enable the recording of deep brain activity during the tasks.
The results of this study will improve our understanding of how different brain circuits support speech learning and production. In particular, this study will help to differentiate the roles of the STN and VIM in learning the ordering of speech sounds within a syllable from learning of speech sequences containing multiple syllables. This knowledge may help guide future approaches to optimizing DBS settings to improve both movement and speech outcomes in individuals with neurological disorders, as well as provide greater general insight into how these brain structures contribute to speech production and learning.
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Subthalamic nucleus with subsyllabic learning arm | Experimental | Behavioral: Phoneme sequence learning, Other: Cessation and re-enabling of stimulation of the STNArm 1: subjects with implanted STN deep brain stimulators will undergo learning tasks involving non-English sound sequences while their stimulators are turned on and off |
| Subthalamic nucleus with multisyllabic learning arm | Experimental | Other: Cessation and re-enabling of stimulation of the STN, Behavioral: Multisyllabic sequence learningArm 2: subjects with implanted STN deep brain stimulators will undergo learning tasks involving syllable sequences while their stimulators are turned on and off |
| Ventral intermediate thalamus with subsyllabic learning arm | Experimental | Behavioral: Phoneme sequence learning, Other: Cessation and re-enabling of stimulation of the VIM thalamic nucleusArm 3: subjects with implanted VIM deep brain stimulators will undergo learning tasks involving non-English sound sequences while their stimulators are turned on and off |
| Ventral intermediate thalamus with multisyllabic learning arm | Experimental | Other: Cessation and re-enabling of stimulation of the VIM thalamic nucleus, Behavioral: Multisyllabic sequence learningArm 4: subjects with implanted VIM deep brain stimulators will undergo learning tasks involving syllable sequences while their stimulators are turned on and off |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (10 listed)
- 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)
Key exclusion criteria (8 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Phoneme sequence learningApproximately half of subjects enrolled in the study will participate in this intervention. Subjects will read aloud monosyllabic sequences that are presented orthographically on a screen. Each sequence is formed by a non-native consonant cluster followed by a vowel and final consonant (CCVC). Speech trials will be grouped into blocks. After a Familiarization block, subjects will produce a set of twelve CCVCs in a Pretest block. Subjects will then repeatedly produce two of those CCVCs in one Training block, and two other CCVCs in a subsequent Training block. Following training, subjects will produce all four trained CCVCs and four additional novel CCVCs in each of two Test blocks. Washout blocks, during which no speech task trials are completed, will follow the Pretest, Training, and first Test block to allow subjects to rest and to complete standardized testing. | Behavioural | Subthalamic nucleus with subsyllabic learning arm, Ventral intermediate thalamus with subsyllabic learning arm |
| Cessation and re-enabling of stimulation of the STN20 adults with Parkinson's disease (PD) who have deep brain stimulator (DBS) implants in the subthalamic nucleus (STN). Stimulation of the STN will be intermittently turned off while subjects complete speech sequence learning tasks. After no more than 35 minutes, stimulation will be re-enabled with normal clinical parameters for each participant. | Other | Subthalamic nucleus with multisyllabic learning arm, Subthalamic nucleus with subsyllabic learning arm |
| Cessation and re-enabling of stimulation of the VIM thalamic nucleus20 adults with essential tremor who have deep brain stimulator (DBS) implants in the ventral intermediate nucleus (VIM) of the thalamus will participate in this intervention. Stimulation of the VIM will be intermittently turned off (DBS OFF state) while subjects complete speech sequence learning tasks. After no more than 35 minutes, stimulation will be re-enabled with normal clinical parameters for each participant. | Other | Ventral intermediate thalamus with multisyllabic learning arm, Ventral intermediate thalamus with subsyllabic learning arm |
| Multisyllabic sequence learningApproximately half of subjects enrolled in the study will participate in this intervention. Subjects will read aloud sequences that are presented orthographically on a screen. Speech trials will be grouped into blocks. After a Familiarization block, subjects will produce 2- and 7-syllable sequences in an Assessment block to determine the appropriate length sequence for the remainder of the intervention. Subjects will produce a set of eight sequences in a Pretest block. Subjects will then repeatedly produce two of those sequences in one Training block and two other sequences in a subsequent Training block. Following training, subjects will produce all four trained sequences and two additional novel sequences in each of two Test blocks. Washout blocks, during which no speech task trials are completed, will follow the Pretest, Training, and first Test Block to allow subjects to rest and to complete standardized testing. | Behavioural | Subthalamic nucleus with multisyllabic learning arm, Ventral intermediate thalamus with multisyllabic learning arm |
Primary outcome
Change in speech sequencing accuracy
Time frame: Day 1
Investigators will evaluate recordings of speech productions to identify errors. This will be used to compare sequence accuracy before and after practice of novel sequences with DBS in the ON and OFF states.
Speech production duration
Time frame: Day 1
Investigators will inspect recordings of speech productions to identify production duration. This will be used to test hypotheses regarding differences in sequence duration before and after practice of novel sequences and with DBS in the ON and OFF states.
Beta power during speech production
Time frame: Day 1
Investigators will extract beta band (12-20 Hz) power from neural recordings taken while subjects practice and rehearse novel speech sequences. This will be used to test hypotheses regarding differences in beta power before and after practice of novel sequences and with DBS in the ON and OFF states.
4 secondary outcomes
Cognitive Assessment
Time frame: Baseline
Forward Digit Span
Time frame: Baseline
Essential tremor severity
Time frame: Day 1
Parkinson's disease severity
Time frame: Day 1
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Mar 2026.
- Individual participant dataSharing planned: No. All planned analyses will be carried out by research staff who are already facilitating the study.
Related trials for Parkinson's Disease (PD)
Active, not recruitingPhase 1/2
Clinical Safety and Efficacy of Umbilical Cord Mesenchymal Stromal Cells-derived Exosomes in Patients With Parkinson's Disease
Parkinson Disease (PD)
Active, not recruitingObservational study
Adaptive DBS to Offset STN Dysregulation During Exercise in PD
Parkinson Disease
Not yet recruiting
Evaluating the Effect of the Zeen Mobility Device on Clinical Practicality, Safety, and Impact (Via Assessments of Walking, Standing Tolerance, Balance, Endurance, Effort, and Participation in Daily Tasks) in an Outpatient Rehabilitation Setting for Individuals With Mobility Impairments.
Stroke, Parkinson's Disease (PD)
RecruitingObservational study
Striatal and Extra-Striatal Cholinergic Terminal Density in LRRK2-PD Mutation
Parkinson Disease
Not yet recruiting
Unilateral and Staged Bilateral Pallidothalamic Tractotomy Using Exablate MRgFUS in Advanced Parkinson's Disease.
Parkinson Disease
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Frank H Guenther, Ph.D. principal investigator
Boston University
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Phoneme sequence learning, Cessation and re-enabling of stimulation of the STN and Cessation and re-enabling of stimulation of the VIM thalamic nucleus in people with Parkinson's Disease (PD) and Essential Tremor, run by Boston University Charles River Campus at 2 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 10 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 9 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Frank H Guenther, Ph.D. (617-353-5765, guenther@bu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in speech sequencing accuracy (time frame: Day 1). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Mar 2026.