Hippocampal Temporal Interference Stimulation for Memory and Dual-Task Postural Control in Older Adults With Mild Cognitive Impairment

Effects and Underlying Mechanisms of Hippocampal-Targeted Temporal Interference Stimulation on Memory Function and Dual-Task Postural Control in Older Adults With Mild Cognitive Impairment

This trial aims to investigate whether a single session of 40 Hz hippocampal temporal interference stimulation can improve memory function and dual-task postural control among older adults with mild cognitive impairment (MCI). The primary research questions to be addressed are as follows:

• Can 40 Hz hippocampal temporal interference stimulation boost memory test performance in older adults with MCI?
• Can 40 Hz hippocampal temporal interference stimulation improve walking and balance ability under dual-task conditions in older adults with MCI? Researchers will compare active 40 Hz hippocampal temporal interference stimulation against sham stimulation to identify whether this intervention yields positive immediate effects on memory function and dual-task postural control.

Participants will be required to:

• Attend three laboratory visits over approximately three weeks, and receive one session of active stimulation and one session of sham stimulation in random order, with an interval of at least seven days between the two stimulation visits;
• Complete memory and motor function assessments before and after each stimulation session;
• Undergo functional magnetic resonance imaging (fMRI) scans to detect changes in brain activity.

1. Aged 65 years or older;
2. Presence of subjective memory complaints;
3. Objective cognitive impairment: screened using the Montreal Cognitive Assessment-Bejingversion (MoCA-BJ). The MoCA-BJ total score is 30 points. For individuals with <12 years ofeducation, 1 point is added to the raw total score (corrected total score capped at 30 points); acorrected total score <26 points indicates risk of cognitive impairment;
4. Clinical Dementia Rating (CDR) score of 0.5;
5. Does not meet diagnostic criteria for dementia: Mini-Mental State Examination (MMSE) scores>18 for illiterate individuals, 221 for those with primary school education, and >25 for those withjunior high school education or above;6. Retains independent activities of daily living (ADL) and is capable of cooperating with allassessments and interventions.