Effects and Mechanisms of Temporal Interference Brain Stimulation on Memory Function in Preclinical Alzheimer's Disease

Capital Medical University

Status: Enrolling

Conditions: Alzheimer Disease

Treatments: Device: Sham TIBS; Device: Active TIBS

Study type: Interventional

Funder types: Other

Identifiers

NCT07031687

TIBS_hanying_0605

Details and patient eligibility

About

The goal of this clinical trial is to learn if personalized, multimodal imaging-guided, EEG-based closed-loop Temporal Interference Brain Stimulation (TIBS) can improve memory function in individuals with preclinical Alzheimer's Disease (AD).

The main questions it aims to answer are:

1. Does personalized TIBS lead to significant changes in functional connectivity strength of hippocampal-cortical networks at the end of the 2-week intervention compared to baseline?
2. What are the short-term (end of 2-week intervention) and medium-to-long-term (4 weeks and 12 weeks post-intervention) effects of personalized TIBS on episodic and working memory, as well as other cognitive domains in preclinical AD?
3. How does personalized TIBS modulate brain activity and connectivity, as measured by EEG power spectra and functional MRI (fMRI) functional connectivity, in preclinical AD?
4. What is the safety profile of personalized TIBS in this population?

Researchers will compare participants receiving active personalized TIBS to participants receiving sham (inactive) stimulation to see if TIBS effectively improves memory function and induces neural plasticity.

Participants will:

1. Undergo initial screening including neuropsychological assessments and blood p-tau217 testing to identify preclinical AD.
2. Receive either active personalized TIBS or sham stimulation daily for 40 minutes, 6 days a week, for 2 weeks.
3. Have individualized TIBS parameters (e.g., target localization, intensity) determined using baseline structural MRI and DTI.
4. Undergo real-time high-density EEG monitoring during daily stimulation sessions to enable closed-loop adjustment of stimulation parameters.
5. Participate in follow-up assessments at the end of the 2-week intervention, and at 4 weeks and 12 weeks post-intervention.
6. Receive multimodal imaging (sMRI, rs-fMRI, task-fMRI, DTI) and blood biomarker assessments at various time points.
7. Receive Aβ-PET and tau-PET scans, along with comprehensive neuropsychological assessments, at the 12-week follow-up.
8. Have their safety continuously monitored throughout the study.

Enrollment: 1,200 estimated patients

Sex: All

Ages: 60 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Individuals recruited from neurology memory clinics or communities.
• Age between 60 and 80 years old, inclusive; no gender limitation.
• Right-handed.
• Cognitive function test results within normal range after age, gender, and education-level adjustment, OR mild cognitive impairment not yet meeting diagnostic criteria for Mild Cognitive Impairment (MCI), OR only subjective cognitive decline.
• Individuals classified as preclinical AD based on the revised 2024 AD diagnostic and staging criteria (i.e., cognitively normal with positive plasma p-tau217 or positive Aβ PET).
• Full understanding of the study, voluntary participation, and provision of written informed consent approved by the Ethics Committee.

Exclusion criteria

• Past or present neurological diseases (e.g., stroke, epilepsy, Parkinson's disease, multiple sclerosis).
• Psychiatric disorders such as severe depression or severe anxiety.
• Systemic diseases causing cognitive decline (e.g., severe thyroid dysfunction, severe liver or kidney disease, severe nutritional deficiencies).
• Currently taking medications that may affect cognitive function (e.g., anticholinergics, benzodiazepines, antipsychotics) that cannot be discontinued or adjusted.
• Other factors leading to cognitive decline that are not AD-related.
• Contraindications for MRI scans, such as claustrophobia, implanted metallic devices (e.g., pacemakers, cochlear implants, aneurysm clips), or history of head injury with retained metal fragments.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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1,200 participants in 2 patient groups

Personalized Closed-Loop Temporal Interference Brain Stimulation

Experimental group

Description:

Participants in this arm will receive active TIBS targeted at the bilateral hippocampus. Stimulation parameters include a 5 Hz (Theta band) low-frequency modulation envelope, generated by two high-frequency current pairs (e.g., f1=2000 Hz, f2=2005 Hz). Peak-to-peak current intensity for each pair will be 2 mA (or 1 mA per electrode). Stimulation will be delivered daily for 40 minutes, 6 days/week, for a total of 2 weeks. Individualized targeting and initial intensity optimization will be guided by baseline sMRI and DTI. Real-time high-density EEG monitoring during each daily session (D2-D11) will provide feedback on brain activity (e.g., EEG power spectra, functional connectivity features) to enable closed-loop optimization of transcranial stimulation intensity and phase parameters.

Treatment:

Device: Active TIBS

Sham Temporal Interference Brain Stimulation

Sham Comparator group

Description:

Participants in this arm will receive sham stimulation designed to mimic the sensation of active TIBS without therapeutic output. This will involve using a sham coil or a device mode with extremely low current intensity (e.g., 0.1-0.2 mA) or brief ramp-up/ramp-down sensations at the beginning and end of sessions, with no effective current delivery during the main stimulation period. The stimulation position and apparent parameters will be identical to the active TIBS group to maintain blinding.

Treatment:

Device: Sham TIBS