NCT07498270 · University of Wisconsin, Madison
Location- and Frequency-Dependent Effects of Thalamic Temporal Interference Stimulation During Sleep
(CAP-TI)
What this study is about
This study is to find out whether a type of non-invasive electrical brain stimulation called temporal interference transcranial electrical stimulation (TI-TES) can temporarily change brain activity during sleep, especially sleep spindles (brain rhythms in the \~8-16 Hz range). Up to 24 healthy participants in Dane County, Wisconsin will be enrolled for 3 overnight study visits.
View original scientific description
This study is to find out whether a type of non-invasive electrical brain stimulation called temporal interference transcranial electrical stimulation (TI-TES) can temporarily change brain activity during sleep, especially sleep spindles (brain rhythms in the \~8-16 Hz range). Up to 24 healthy participants in Dane County, Wisconsin will be enrolled for 3 overnight study visits. Participants can expect to be on study for approximately 5 weeks, depending on scheduling availability.
Interventions
OTHER
Magnetic Resonance Imaging (MRI)
MRI is to optimize placement of uni- or multipolar TI-TES
DEVICE
Broad thalamic stimulation (TI-TES)
Stimulation targeted at the whole thalamus. Within each overnight session, up to 24 stimulation protocols will be administered, randomized across frequencies (including SHAM). Stimulation will be initiated by trained sleep technicians during stable N2 sleep and delivered in 3-minute epochs separated by 6-minute intervals to enable comparison of PRE, STIM, and POST intervals
DEVICE
Carrier only SHAM stimulation
Carrier only SHAM condition. Within each overnight session, up to 24 stimulation protocols will be administered, randomized across frequencies (including SHAM). Stimulation will be initiated by trained sleep technicians during stable N2 sleep and delivered in 3-minute epochs separated by 6-minute intervals to enable comparison of PRE, STIM, and POST intervals
DEVICE
Anterior thalamic stimulation (TI-TES)
Stimulation targeted at the anterior thalamus. Within each overnight session, up to 24 stimulation protocols will be administered, randomized across frequencies (including SHAM). Stimulation will be initiated by trained sleep technicians during stable N2 sleep and delivered in 3-minute epochs separated by 6-minute intervals to enable comparison of PRE, STIM, and POST intervals
DEVICE
Posterior thalamic stimulation (TI-TES)
Stimulation targeted at the posterior thalamus. Within each overnight session, up to 24 stimulation protocols will be administered, randomized across frequencies (including SHAM). Stimulation will be initiated by trained sleep technicians during stable N2 sleep and delivered in 3-minute epochs separated by 6-minute intervals to enable comparison of PRE, STIM, and POST intervals.
Primary outcome measures
Change in Spectral Power (SFA) for Active TI-TES vs SHAM
Time frame: during each of the 3 overnight visits, 5 weeks
Comparing active TI-TES vs carrier only SHAM, evaluated using both STIM-PRE and POST-PRE contrasts.
Change in SFA by Location
Time frame: during each of the 3 overnight visits, 5 weeks
Changes in 8-16 Hz spectral power across frequency-location combinations (broad thalamic, anterior thalamic, posterior thalamic) for STIM-PRE and POST-PRE to identify the most effective parameters within the tested parameter space.
Spindle Density in slow (8-12 Hz) and fast (13-16 Hz) SFA
Time frame: during each of the 3 overnight visits, 5 weeks
Changes in slow (8-12 Hz) and fast (13-16 Hz) spindle characteristics (density) using STIM-PRE and POST-PRE contrasts
Spindle Amplitude in slow (8-12 Hz) and fast (13-16 Hz) SFA
Time frame: during each of the 3 overnight visits, 5 weeks
Changes in slow (8-12 Hz) and fast (13-16 Hz) spindle characteristics (amplitude) using STIM-PRE and POST-PRE contrasts
Spindle Duration in slow (8-12 Hz) and fast (13-16 Hz) SFA
Time frame: during each of the 3 overnight visits, 5 weeks
Changes in slow (8-12 Hz) and fast (13-16 Hz) spindle characteristics (duration) using STIM-PRE and POST-PRE contrasts
Spindle Topography in slow (8-12 Hz) and fast (13-16 Hz) SFA
Time frame: during each of the 3 overnight visits, 5 weeks
Changes in slow (8-12 Hz) and fast (13-16 Hz) spindle characteristics (topography) using STIM-PRE and POST-PRE contrasts
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
- Medically healthy (based on self-report and study team review)
- U.S. citizen or holding permanent resident status
- English-speaking (able to provide consent and complete questionnaires)
Exclusion criteria
- Any current or past history of neurological disorders or acquired neurological disease (e.g. stroke, traumatic brain injury), including intracranial lesions (including clinically significant findings identified in first MRI)
- History of inpatient psychiatric hospitalization
- History of head trauma resulting in prolonged loss of consciousness; or a history of greater than 3 grade I concussions
- Current history of poorly controlled headaches including intractable or poorly controlled migraines
- Any systemic illness or unstable medical condition that may cause a medical emergency in case of a provoked seizure (cardiac malformation, cardiac dysrhythmia, asthma, etc.)
- History of seizures, diagnosis of epilepsy, history of abnormal (epileptiform) EEG, or family history of treatment resistant epilepsy except for a single seizure of benign etiology (e.g. febrile seizures) in the judgment of a board-certified neurologist
- Possible pregnancy or plan to become pregnant in the next 6 months (self reported)
- Any metal in the head
- Any medical devices or implants (i.e. cardiac pacemaker, medication infusion pump, cochlear implant, vagal nerve stimulator)
- Dental implants
- Permanent retainers
- Any hair braid, dreadlocks, hair pieces, or extensions which cannot be taken out before the study sessions
- Any head coverings or headdress that participant feels uncomfortable removing for the purposes of study sessions
- Any medication that may alter seizure threshold taken during the study i.e., ADHD stimulants (Adderall, amphetamine); Tricyclic/atypical antidepressants (amitriptyline, doxepine, imipramine, maprotiline, nortriptyline, bupropion); SSRIs (Escitalopram, Fluoxetine, Sertraline); Antipsychotics (chlorpromazine, clozapine), Bronchodilators (theophylline, aminophylline); Antibiotics (fluoroquinolones, imipenem, penicillin, cephalosporins, metronidazole, isoniazid); Antivirals (valacyclovir, ritonavir); OTC antihistamines (diphenhydramine, Benadryl)
- Claustrophobia (a fear of small or closed places)
- Back problems that would prevent lying flat for up to two hours
- Regular night-shift work (second or third shift)
- Sleep apnea or other sleep disorder (self-reported)
Where
- Madison, Wisconsin
Collaborators
National Institute of Mental Health (NIMH)
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 Aug 10, 2026 · Source of record for eligibility and locations