Before the second recurrence of cerebral infarction, some patients may have precursors, which mainly depend on the site of infarction. The description is as follows: 1. In the case of cerebral infarction caused by lesions in the internal carotid artery system, most patients can show episodes of sensory impairment and motor impairment in the lateral limbs, and may also develop hemianopia, and some patients may also develop psychiatric symptoms. 2. 3. In case of cerebellar and brainstem infarction caused by lesions of the vertebrobasilar system, most patients may experience dizziness, nausea, vomiting, balance disorders and ataxia, and some patients may also experience episodes of dysphagia, choking and coughing, nystagmus, diplopia, etc. Patients with these symptoms should be treated with oral aspirin or clopidogrel and, if necessary, anticoagulants.