Theta-burst Stimulation on Cognitive Function in the Patients With Young-onset Alzheimer's Disease Dementia

The investigators apply the National Institute on Aging-Alzheimer's Association (NIA-AA) criteria to recruit the biomarker-defined, young-onset AD patients with intermediate-to-high levels of biological evidence. This is a randomized, sham-controlled, 2-way crossover study, and combined neuroimaging study of 18F-2-fluoro-2-deoxy-D-glucose fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) to further explore the potential mechanisms. This study will consist of two intervention periods. A total of 50 young-onset AD patients will be consecutively recruited and be randomized into one of two groups: active and sham stimulation (n = 25 per group) in every intervention period. Besides, 20 cognitively normal subjects will be recruited for neuroimaging comparison. Cognitive evaluation will be performed before and immediately after treatment at 2 weeks of TBS intervention, and 4 weeks after TBS. Data on functional neuroimaging will be also collected before and after TBS protocol.