There are many causes of cerebral infarction, but the most common in clinical practice is the narrowing or occlusion of the carotid artery. Since the brain is supplied by four blood vessels, any issues with any of these vessels can potentially lead to a cerebral infarction. Conditions commonly known as the "three highs"—high blood pressure, high blood sugar, and high cholesterol—can easily lead to narrowing or even blockage of the blood vessels. Thus, these factors are fundamentally the cause. Additionally, smoking and drinking can also lead to vascular narrowing and cause cerebral infarction. In some special cases, autoimmune diseases can cause inflammation inside the vessels, leading to narrowing. Other causes include arterial tears due to trauma, which can lead to ischemia and infarction, or abnormal blood supply due to arrhythmias causing cerebral infarction.