NCT05471960 · University of Minnesota
Neuroplasticity in RBD
What this study is about
REM sleep behavior disorder is a parasomnia that reflects the presence of alpha-synucleinopathy in the brain and is highly predictive of eventual phenoconversion to Parkinson's disease, dementia with Lewy bodies, or multiple system atrophy over the course of years to decades.
View original scientific description
REM sleep behavior disorder is a parasomnia that reflects the presence of alpha-synucleinopathy in the brain and is highly predictive of eventual phenoconversion to Parkinson's disease, dementia with Lewy bodies, or multiple system atrophy over the course of years to decades. Neuroplastic adaptations in the brain during the prodromal stage of disease are thought to mask the expression of motor and non-motor signs and may substantially delay diagnosis during a potentially critical time window. This study will examine the state and progression (over 30 to 36 months) of neuroplastic changes in the excitability of the motor and prefrontal cortex (using transcranial magnetic stimulation), the structural and functional connectivity of the brain (using highfield, 7T, magnetic resonance imaging), and the relationship of these changes to the expression of motor and neuropsychological signs, in a cohort of individuals with REM sleep behavior disorder and matched controls.
Interventions
OTHER
Natural progression over time
Each subject will attend eight testing sessions (MRI scanning, two TMS-motor test visits, two TMS-prefrontal test visits, motor assessments, neuropsychological testing, and overnight sleep testing (polysomnography - PSG).
Primary outcome measures
MRI Progression over 30 to 36 months
Time frame: 30 to 36 months from baseline
Yes/No whether a change was observed from baseline
Change in Beck Depression Inventory score
Time frame: 30 to 36 months from baseline
Higher score means more impairment
Change in Mattis Dementia Rating Scale
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in Rey Complex Figure
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in WAIS-IV Matrix Reasoning
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in Stroop Color
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in Stroop Word
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in Stroop Color Word
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in Wisconsin Card Sorting Test
Time frame: 30 to 36 months from baseline
Higher score means more impairment for subsections "# persev errors" and FMS; less impairment for subsections "# categories" and conceptualization
Change in D-KEFS
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in BVMT-R
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in HVLT
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in WMS-3 Spatial Span
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in Boston Naming Test
Time frame: 30 to 36 months from baseline
Higher score means less impairment
Change in Trail Making Test A
Time frame: 30 to 36 months from baseline
Higher score means more impairment
Change in Trail Making Test B
Time frame: 30 to 36 months from baseline
Higher score means more impairment
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- for the iRBD Group:
- Diagnosis of polysomnogram-confirmed isolated iRBD.
- Able to ambulate independently without the use of an assistive device (e.g., cane) for 50 meters.
- Age: 21-75 years. Inclusion Criteria For Control Subject Group:
- Age: 21-75 years.
- Able to ambulate independently without the use of an assistive device (e.g., cane or walker for 50 meters.
Exclusion criteria
- for iRBD group:
- Dementia diagnosis and/or a University of California Brief Assessment of Capacity to Consent (UBACC) score and MacCAT-CR score indicating impaired capacity to consent.
- History of musculoskeletal disorders that significant affect movement of lower or upper limbs as determined at the time of enrollment.
- Other significant neurological disorders that may affect participation or performance in the study.
- Anti-depressant associated RBD. Individuals will be excluded if their dream enactment emerged or clearly worsened after initiating an antidepressant medication.
- Meet criteria for overt Parkinson's disease, dementia with Lewy bodies, Multiple Systems Atrophy, Alzheimer's disease, or other neurodegenerative disorder, or other known cause of RBD (e.g., narcolepsy and drug induced RBD).
- Untreated sleep-disordered breathing
- History of musculoskeletal disorders that significantly affect movement of lower or upper limbs as determined at the time of enrollment.
- Pregnant women
- Additional exclusion criteria for TMS experiments (note that individuals who are excluded from the TMS experiment still have the opportunity to participate in the other data collection sessions):
- History of seizures, epilepsy, stroke, multiple sclerosis, or traumatic brain injury
- Recent history of frequent syncope (fainting) episodes in response to blood, emotional stress, or sensory triggers.
- Intracranial metallic or magnetic devices (e.g. cochlear implant, deep brain stimulator)
- Pacemaker or any implanted device
- History of surgery on blood vessels, brain, or heart
- Unexplained, recurring headaches or concussion within the last six months
- Severe hearing impairment
- If participant is taking one of the following medications that affects neuroplasticity testing, they will be excluded from the TMS experiment: haloperidol (dopamine antagonist), prazosin (norepinephrine antagonist), biperiden (acetylcholine antagonist), dopamine modulators, NMDA receptor and calcium channel modulators, GABAergic drugs (benzodiazepines), lithium, lovastatin, and cannabis. Exclusion Criteria for Control subject Group:
- Same as exclusion criteria as the iRBD group
- History of dream enactment from either patient report or from a bed partner witness that may suggest iRBD.
- History of untreated sleep-disordered breathing.
- Presence of parkinsonism or cognitive impairment (including dementia or mild cognitive impairment).
- Active central nervous system, systemic, psychiatric conditions or use of psychoactive medication that would adversely affect cognitive, neuropsychiatric, motor, or autonomic functioning
Where
- Minneapolis, Minnesota
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 10, 2026 · Source of record for eligibility and locations