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

Brief Summary

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.