Fig. 1From: Brain mechanisms underlying neuropsychiatric symptoms in Alzheimer’s disease: a systematic review of symptom-general and –specific lesion patternsSchematic diagram of the onset time of NPSs. Disease progression is divided into five stages: healthy stage, preclinical AD or aMCI, mild AD, moderate AD, and severe AD. Each rise of the curve represents a significant increase in the prevalence of the NPSs compared to the previous stage. Abbreviations: AD, Alzheimer’s disease; aMCI, amnestic mild cognitive impairmentBack to article page