Sleeping with the window open generally does not cause the patient to have a stroke, but from the Chinese medicine point of view understanding, if the gap of the open window is relatively small, there is the invasion of deficiency evil and thieves wind, coupled with the deficiency of the body’s righteousness, it may cause the patient to have a stroke, also known as hanging line wind, facial paralysis. From a western medical point of view, the stroke is due to the patient’s face being cooled and blown by the wind, while low resistance leads to viral infection of the facial nerve, and the crooked corners of the mouth, as well as incomplete eyelid closure and cheek puffing and leakage, also known as mini-stroke. So if you sleep with the window open in summer, try to block the window with curtains to avoid the invasion of false evil and thieving wind. If a person has a normal constitution and normal resistance, even if there is a very small slit in the open window, it will not lead to facial neuritis because of blowing wind. Once a patient has symptoms of facial neuritis because of an open window, he or she needs to see a hospital for treatment in a timely manner.