NCT07498270

Location- and Frequency-Dependent Effects of Thalamic Temporal Interference Stimulation During Sleep

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 24 (estimated)
• Sponsor: University of Wisconsin, Madison · Academic / Other
• Sex: All
• Age: 18 Years – 40 Years
• Healthy volunteers: Accepted

Summary

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.

Detailed description

This single-site, single-blind, experimental study will test whether thalamic temporal interference transcranial electrical stimulation (TI-TES) delivered during Non-Rapid Eye Movement (NREM) sleep can enhance spindle-frequency activity (SFA) in healthy adults and identify optimal stimulation parameters across frequency and thalamic target location. After screening/consent, participants will complete a structural MRI for personalized montage optimization, then undergo three overnight High-Density Electroencephalography (hdEEG) and Polysomnography (PSG) sleep sessions (10-12 hours each) in a randomized, counterbalanced crossover design, one session per stimulation location (broad thalamic, anterior thalamic, posterior thalamic). During stable N2 sleep, TI-TES will be delivered in 3-minute epochs separated by 6-minute intervals, for up to 24 epochs per night, under real-time sleep-technician monitoring. The study uses a two-phase frequency plan: Phase 1 (\~10 participants) will test 10 Hz, 14 Hz, and matched carrier-only SHAM; contingent on feasibility/sensitivity, Phase 2 (\~10 participants) will expand frequencies across 8-16 Hz. Primary outcomes quantify stimulation-related increases in 8-16 Hz spectral power (SFA) and spindle characteristics comparing active TI-TES versus SHAM and across stimulation locations/frequencies. Primary Objectives: 1. Determine whether active thalamic TI-TES increases 8-16 Hz spindle-frequency activity (SFA) relative to carrier-only SHAM (evaluated using STIM-PRE and POST-PRE contrasts). 2. Identify the most effective TI-TES stimulation parameters across stimulation frequencies and stimulation locations (broad thalamic, anterior, posterior) by comparing SFA changes across parameter combinations. 3. Characterize stimulation-related changes in spindle characteristics (density, amplitude, duration, topography) for slow and fast spindle subtypes. Secondary Objectives: 4. Evaluate stimulation-related changes in slow (8-12 Hz) and fast (13-16 Hz) spindle spectral power. 5. Evaluate stimulation-related changes in slow wave (0.5-4.0 Hz) spectral power. 6. Characterize stimulation-related changes in slow-wave characteristics (density, amplitude, duration). 7. Evaluate stimulation-related changes in SO-spindle coupling (phase-amplitude coupling) for slow and fast spindles. 8. (Exploratory) Evaluate stimulation-related changes in hdEEG functional connectivity between channels using the phase slope index (PSI).

Conditions

• Healthy Adult Participants
• Healthy Participants

Interventions

Type	Name	Description
OTHER	Magnetic Resonance Imaging (MRI)	MRI is to optimize placement of 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.

Timeline

• Start date: 2026-04-01
• Primary completion: 2027-08-01
• Completion: 2028-02-01
• First posted: 2026-03-27
• Last updated: 2026-04-02

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated device study