High-frequency tRNS for Sleep Disturbances in Neurocognitive Disorders Due to Vascular Disease

The investigators aim to 1) investigate and compare the safety, efficacy and sustainability of hf-tRNS, tACS and sham transcranial current stimulation (tCS) over left inferior parietal lobe (IPL) in mild neurocognitive disorder due to vascular disease (NCD-vascular) patients with sleep disturbances; 2) examine the relationship between the changes in sleep quality, cognitive function and brain morphometry. Methods: Chinese right-handed mild NCD-AD patients with sleep disturbances (aged from 60 to 90 years) will be randomly assigned to a 2-week intervention of either hf-tRNS, tACS, or sham tCS, with 10 participants per arm. Before intervention, structural magnetic resonance imaging (MRI) data is used to construct individual realistic head model. Comprehensive assessments, including sleep quality, cognitive performance and blood pressure will be conducted at baseline, 2th week, 6th week and 12th week. Program adherence and adverse effects will be monitored throughout intervention.