If a middle-aged or elderly patient has hypertension or diabetes mellitus and has numbness of the head and face, along with weakness of one limb, it is necessary to consider the possible existence of acute cerebral infarction, and a cranial magnetic resonance examination is needed to clarify. If a young patient has numbness in the head, and the numbness is paroxysmal and of irregular duration, and if it is accompanied by changes in temperament and personality, as well as physical discomfort, such as panic, chest tightness, or shortness of breath, then a functional disease may be considered. Some patients with cervical spondylosis may also experience numbness of the scalp, so hair numbness is not necessarily a precursor of cerebral infarction.