There are many possible causes of involuntary slight shaking of the head to the left and right, and the examinations are performed for the etiology. The most basic examination is to perfect the cranial MRI as well as the EEG, because the MRI can detect the presence of cerebral infarction, cerebral atrophy, neurological degeneration or multiple sclerosis, encephalitis and other diseases in the brain, while the EEG plays an auxiliary diagnostic role. The above-mentioned diseases most often cause head tremor, and there are other causes, such as anger, emotional shock, overexertion, and strenuous exercise, which are functional and have no abnormalities on examination. There are also dance-like movements that can cause involuntary movements, and patients may have tumors, inflammatory diseases, rheumatism, syphilis, etc. Therefore, it is necessary to improve the examination of blood-related immune inflammatory indicators, such as immune decad, blood sedimentation, C-reactive protein, anti-O, and ANA16. Hyperthyroidism can also cause head tremors, so check thyroid hormones as well as T-series antibodies, etc. as well.