Overview
This study aims to evaluate whether individualized hippocampal transcranial temporal interference stimulation (tTIS) combined with Tai Chi training can improve cognitive function and dual-task performance in individuals with mild cognitive impairment. Participants will be randomly assigned to receive either active or sham individualized tTIS combined with Tai Chi training for 8 weeks. The study will also investigate changes in brain structure and function using neuroimaging and assess whether the intervention effects are maintained during follow-up.
Description
This is a randomized, quadruple-blind, sham-controlled, parallel-group trial involving approximately 120 individuals aged 60-80 years with mild cognitive impairment. Participants will be randomly assigned to receive either active or sham individualized transcranial temporal interference stimulation (tTIS) combined with Tai Chi training for 8 weeks, three sessions per week. Individualized tTIS will target the left hippocampus based on participant-specific T1-weighted MRI and finite element modeling, using a 5-Hz interference frequency generated by 2000- and 2005-Hz carrier frequencies at an intensity of 2 mA for 20 minutes per session; each Tai Chi session will last approximately 60 minutes. Global cognition, episodic memory, neuropsychiatric symptoms, functional status, and health-related quality of life will be assessed at baseline, after the 8-week intervention, and at a 16-week post-intervention follow-up. Working memory and executive control, dual-task performance, and neuroimaging outcomes will be assessed at baseline and after the 8-week intervention, with safety, tolerability, and blinding effectiveness monitored throughout the study.
Eligibility
Inclusion Criteria:
- Age 60-80 years
- Community-dwelling
- Montreal Cognitive Assessment (MoCA) score \< 26
- Clinical Dementia Rating (CDR) score = 0.5
- Activities of Daily Living (ADL) score \< 26 (largely intact daily function)
- Does not meet criteria for dementia diagnosis (based on DSM-5 or NIA-AA criteria)
- No contraindications for MRI examination (no metallic implants, no claustrophobia)
- Able to provide written informed consent
Exclusion Criteria:
- Neurological conditions that may cause cognitive decline (e.g., cerebrovascular disease, encephalitis, Parkinson's disease, Huntington's disease)
- Severe visual, auditory, or language impairments preventing completion of neuropsychological assessments
- Severe depression (Geriatric Depression Scale \> 10) or other major psychiatric disorders
- History of seizures or epilepsy
- Previous deep brain stimulation or electroconvulsive therapy within 6 months
- Alcohol or substance dependence
- Concurrent participation in another interventional clinical trial
- Contraindications for non-invasive brain stimulation: electronic or ferromagnetic implants, non-MRI compatible metal implants, history of seizures, pregnancy
