Sometimes numbness in the arm is mainly due to the following reasons: First, if the arm is numb on one side, ask the patient if there is any previous cervical spondylosis. Some patients in cervical disc herniation due to the activity of the upper limbs or incorrect body posture, it is easy to cause intervertebral disc compression nerve and cause arm numbness, then need to do cervical spine magnetic resonance plus electromyography; two, to ask the patient has no limb weakness, arm pain, sleep disorders or anxiety, worry, need to consider the patient exists somatization disorder, can do anxiety scale assessment; three, to ask the patient Previous history of cerebrovascular disease, some patients with cerebral lobe infarction or hemorrhage show focal seizures, and can also show numbness in the arms sometimes, and need to do EEG.