The reason why the scalp is a little numb, may be related to cold stimulation, may also be due to autonomic dysfunction, cerebral arteriosclerosis and other reasons. 1. Cold stimulation: if you stay in a cold environment for a long time, do not pay attention to head warmth, resulting in a prolonged period of cold stimulation of the head, resulting in vasospasm and contraction of the scalp blood vessels, which may cause a bit of numbness of the scalp, and may be accompanied by a slight headache and other symptoms. 2. Autonomic dysfunction: the disease can lead to increased excitability in some areas of the patient’s cerebral cortex, which can cause neurological dysfunction, dysregulation of the autonomic nervous system, which may show a little numbness of the scalp, but also can be accompanied by localized itchy skin, dizziness, panic and other manifestations. 3. Cerebral arteriosclerosis: due to the patient’s blood vessel lumen becomes narrow, blood vessel wall thickening, resulting in the brain tissue blood supply, oxygen supply is insufficient, it may cause a little numbness of the scalp, may also be accompanied by dizziness, headache and other symptoms. Scalp a little numbness, may also be caused by other reasons, if the symptoms occur frequently, or there are other discomfort, should be as early as possible to consult a doctor, diagnose the cause, give targeted treatment.