An interventional study of MRI and TMS in Cerebellar Ataxia, Dysarthria and Healthy, sponsored by University of California, San Francisco. Active, not recruiting at 3 sites in United States. Open to participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-10-24.
Sponsored by University of California, San Francisco · Not applicable, Interventional, and Basic science
This study will investigate the how the cerebellum is involved in speech motor learning over time and short-term corrections in patients with cerebellar ataxia and healthy controls. This will be accomplished through three approaches: behavioral studies, magnetic resonance imaging (MRI), and transcranial magnetic stimulation (TMS). During behavioral studies, participants will be asked to speak into a microphone while their voice is played back over earphones, and to do other speaking tasks. MRI will be acquired to perform a detailed analysis on brain function and anatomy related to speech and the cerebellum. In healthy controls, TMS will also be performed to temporarily disrupt the cerebellum before, during, or after the participant performs speaking tasks. Patients with cerebellar ataxia and healthy volunteers will be asked to complete behavioral studies and/or MRI; healthy volunteers may be asked to additionally participate in TMS.
This study will investigate the role of the cerebellum in speech, building upon prior work in understanding cerebellar function in reaching and walking. Neuroimaging and lesion studies have provided strong evidence that the cerebellum is an integral part of the speech production network, though its precise role in the control of speech remains unclear. Furthermore, damage to the cerebellum (either degenerative or focal) can lead to ataxic dysarthria, a motor speech disorder characterized, in part, by impaired articulation and severe temporal deficits. This project seeks to bridge the gap between theoretical models of cerebellar function and the speech symptoms associated with ataxic dysarthria. Two mechanisms underlie speech motor control - feedback and feedforward control. In feedback control, speakers use sensory feedback (e.g., of their own voice) to control their speech. In feedforward control, speakers use knowledge gained from their past speech productions, rather than on-line feedback, to control their speech. This study entails a systematic plan to elucidate the role of the cerebellum in feedforward and feedback control of speech. A central hypothesis is that the cerebellum is especially critical in the feedforward control of speech, but has little involvement in feedback control. To explore this hypothesis, we will obtain converging evidence from three innovative methodologies: 1) Neuropsychological studies of speech-motor responses to real-time altered auditory feedback in patients with cerebellar atrophy (CA) and matched healthy controls, 2) Parallel studies in healthy controls undergoing theta-burst transcranial magnetic stimulation to create "virtual lesions" of the cerebellum, and 3) Structural and functional studies in CA patients to examine the relationship between cerebellar lesion location, dysarthria symptoms, and feedforward and feedback control ability.
Speech provides an important opportunity to examine how well current theories of cerebellar function generalize to a novel effector (vocal tract) and sensory (auditory) domain. Its purpose for communication imposes exacting spectro-temporal constraints not seen in other motor domains. Furthermore, the distinctive balance of feedback and feedforward control in speech allows us to examine changes in both control types subsequent to cerebellar damage. Critically, this is the first work examining the link between theoretically motivated control deficits in CA patients and the speech symptoms associated with ataxic dysarthria, as well as their neural correlates.
72 studies on the registry are indexed under Cerebellar Ataxia; 16 are open to participants now.
This study's enrollment of 660 is above the median of 25 across 55 interventional studies indexed under Cerebellar Ataxia.
Browse Cerebellar Ataxia studies →University of California, San Francisco is the lead sponsor of 2,169 studies on the registry; 372 are open to participants now.
Of its 267 completed or terminated interventional studies of FDA-regulated products, 202 (76%) have results posted.
Counted across the registry records on this site, refreshed daily.
Inclusion criteria:
Exclusion criteria for healthy volunteers:
Exclusion criteria for participants with cerebellar ataxia (CA):
Exclusion criteria for participants with CA or for healthy volunteers participating in MRI (may still be eligible for other study procedures):
Exclusion criteria for healthy volunteers participating in TMS (may still be eligible for other study procedures):
Exclusion criteria for all potential participants:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Behavioral testing including various speaking tasks Magnetic resonance imaging (MRI)
Diagnostic Test: MRI · Behavioral: Speech-motor behavioral testing
Behavioral testing including various speaking tasks Magnetic resonance imaging (MRI)
Diagnostic Test: MRI · Behavioral: Speech-motor behavioral testing
Behavioral testing including various speaking tasks Magnetic resonance imaging (MRI) Transcranial magnetic stimulation (TMS)
Diagnostic Test: MRI · Device: TMS · Behavioral: Speech-motor behavioral testing
Brain MRI will be performed (no contrast) to correlate brain anatomy/function with behavioral testing.
Also known as: Magnetic Resonance Imaging
Repetitive TMS will be applied to transiently disrupt cerebellar speech pathways.
Also known as: Transcranial Magnetic Stimulation, Repetitive TMS, rTMS
Language/speaking tasks will be performed during which participants are asked to speak in response to audio/video cues; participants' responses will be recorded. For patients with cerebellar ataxia, additional diagnostic surveys may be completed.
Speech-motor response percent compensation
Percent compensation is calculated as the following ratio: -100\*(change in acoustic feature produced by the subject)/(change in acoustic feature caused by auditory feedback alteration). The negative sign ensures that changes produced by the subject that oppose the auditory feedback alteration changes are counted as positive compensation. Acoustic features used to compute percent compensation depend on the experiment performed and will include pitch or formant frequencies of subjects' output speech (measured by frequency in Hz), voice onset time (measured in milliseconds), fricative consonant duration (measured in milliseconds), and formant transition time (measured in milliseconds). We will look for short-term (within-trial) and long-term (across-trial) changes in percent compensation produced by subjects in response to alterations in subjects' auditory feedback they hear while speaking.
Time frame: Baseline
Dysarthria symptoms
Ataxic dysarthria (AD) symptoms will be quantified in patients with cerebellar ataxia (CA) by licensed speech-language pathologists using the Bogenhausen Dysarthria Scales (BoDyS), a dysarthria assessment tool that has been shown to be objective, reliable, and sensitive to dysarthria subtypes 31, 60, and 61. The BoDyS test entails 33 separate component ratings, including symptoms that may be related to feedforward and feedback components of speech motor control systems.
Time frame: Baseline
Voxel-based morphometry (VBM)
VBM will be applied to explore the functional organization of the cerebellum for speech production, focusing on psychophysical measures of speech motor control as well as clinical measures of dysarthric speech symptoms.
Time frame: Baseline
Plan to share: No
This study is active, not recruiting, as verified in Oct 2025. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of California, San Francisco →