Brain topography, a more advanced test, is capable of both pathological and functional diagnosis and is generally superior to conventional EEG. EEG topography, which is a spherical scalp spread into a planar graph with power values in each frequency band of brain waves expressed in different colors, is a reprocessing of EEG. It is mainly used in the early diagnosis of ischemic cerebrovascular disease and evaluation of the prognosis of the treatment, pediatric development and brain wave research, epilepsy, psychiatric diseases and other auxiliary diagnosis.