Alzheimer's disease (AD) is one of the major brain diseases which received more attention in recent years. The disconnection syndrome is the main pathophysiological mechanism leading to cognitive decline in AD patients. Both animal experiment and clinical observation have demonstrated that acupuncture can generate treatment effect on AD patients by moderating the neural pathway directly. However, the underlying mechanism remains unclear. By using resting state functional magnetic resonance imaging (fMRI) method, as well as acupuncture and neurology sciences, investigators will explore the multi-modality data analysis; compare brain connectivity and network parameters changes between pre- and post- acupuncture treatment; analyze the correlation between fMRI changes and neuropsychology test. The present study aims to elucidate the neural mechanism of acupuncture therapy on early AD, provide theoretical evidence from the perspective of functional connectivity.