NCT06267521

The STRENGTHEN Study

Hybrid Interventions to Optimize Neural Plasticity and Enhance Well-being: Mental Exercise, and Transcranial Electrical Stimulation With Temporal Interference: The STRENGTHEN Study - Phase 1 and 2

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 96 (estimated)
• Sponsor: University of Wisconsin, Madison · Academic / Other
• Sex: All
• Age: 18 Years – 50 Years
• Healthy volunteers: Accepted

Summary

This study uses two different types of interventions including electrical brain stimulation delivered during sleep, and brief, daily meditation training. The investigators are trying to figure out whether these techniques, either alone or in combination with each other, can positively impact the brain networks that support our ability to think flexibly and to regulate our emotions. 48 participants will be enrolled into each of 2 phases and can expect to be on study for up to 9 months.

Detailed description

The investigators will evaluate the independent and synergistic effect of Cognitive Flexibility (CF)/Emotional Regulation (ER) - targeted meditation and CF/ER-targeted Transcranial Electrical Stimulation with Temporal Interference (TES-TI) during sleep in low-risk participants (n = 48). After informed consent, all participants will undergo a set of baseline assessments, including self-report measures, behavioral tasks, functional and structural MRI, and a baseline in-laboratory sleep study. Following these assessments, participants undergo four weeks of the study intervention. The participants will be assigned into one of four groups. Each group consists of 12 participants. After completing the 4-week intervention, participants will repeat the behavioral, self-report, and imaging assessments given at baseline. Participants will also complete a 7-day ecological momentary assessment (EMA) at baseline, the week after intervention, and at 4-months following intervention. At the 4-month follow-up, participants may complete another round of self-report and behavioral measures. The Primary Objectives are to: * Evaluate the effects of the following on CF and ER networks: 1. meditation practice alone 2. meditation practice and high-dose TES-TI 3. meditation practice and low-dose TES-TI 4. TES-TI alone The Secondary Objectives are to: * Evaluate the differential synergies between Non-Rapid Eye Movement (NREM) and Rapid Eye Movement (REM) sleep TES-TI intervention and the restoration of CF verses ER circuits For Phase 2, an additional 48 participants will be recruited and will eliminate TES-TI once per week. All participants will come to the sleep laboratory for 2 nights over the 4 week intervention period. Planned interim analysis of slow wave activity data from N=20 participants is adequately powered to evaluate whether TES-TI produces the anticipated modulation of deep sleep.

Conditions

• Cognitive Flexibility
• Emotional Regulation

Interventions

Type	Name	Description
OTHER	Healthy Minds Program	Participants will follow daily instructions from the Healthy Minds Program at home for four weeks, including guided meditation exercises.
OTHER	Sham Meditation Didactic Material	Participants will listen to lessons from the Healthy Minds Program at home for four weeks, which will not include any actual meditation exercises.
DEVICE	Sham Stimulation in Lab	On two nights each week during the four weeks of the intervention, participants will sleep in the lab and undergo sham TES-TI stimulation for approximately 10 hours per night
DEVICE	Stimulation in Lab	Participants will sleep in the lab and undergo active TES-TI stimulation for approximately 10 hours per night.
DEVICE	MRI Scanner	Imaging protocol will include: structural T1-weighted and T2-weighted images, resting-state functional MRI, task-based functional MRI, and multi-shell diffusion weighted MRI, total scan time will be approximately 2 hours

Timeline

• Start date: 2024-03-06
• Primary completion: 2026-04-01
• Completion: 2026-04-01
• First posted: 2024-02-20
• Last updated: 2026-02-04

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated device study