Deep brain stimulation is hopeful in the treatment of AD. There is clinical evidence that deep brain stimulation can effectively postpone, hinder and even reverse the progression of AD. The clinical data also shows that selective atrophy of cholinergic neurons of the nucleus basalis of Meynert (NBM) is one of characteristics of AD. In 1985, Turnbull et al., were the first to report the role of deep brain stimulation of the NBM in AD patients. They detected cortical glucose metabolic activity using FDG-PRT and found that the cortical glucose metabolic activity in the frontal lobe, temporal lobe, parietal lobe, and occipital lobe of the right hemisphere (not stimulated) of AD patients was decreased by 21%, 24%, 10%, and 7.5%, respectively. By contrast, cortical glucose metabolic activity in the left hemisphere was decreased by 12%, 4%, 0 and -1.5% respectively. Although there were no improvements in clinical symptoms, study findings suggest that deep brain stimulation of the NBM is safe and leads to strong pathophysiologic response. Laxton et al. performed deep brain stimulation of the hypothalamus and fornix in six patients with mild AD. At 6 and 12 months after deep brain stimulation, Mini-Mental State Examination (MMSE) and Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog) evaluations showed that patient's cognitive was improved. In the same case cohort, Smith et al. investigated cerebral glucose metabolism and found that deep brain metabolism increased cerebral glucose metabolism mainly through two orthogonal networks: a frontal-temporal-parietal-striatal- thalamic network and a frontal-temporal-parietal-occipital-hippocampal network. Fontaine et al. performed deep brain stimulation in one AD patients presenting with mild cognitive disorder. Twelve months after deep brain stimulation, cerebral glucose metabolism was slightly increased in the cerebrum, in particular in bilateral middle temporal gyri; in addition, cognitive function was improved as confirmed by MMSE and ADAS-Cog evaluations.