The causes of mental unclearness in patients are mainly considered in the following two aspects: 1. Functional causes should be considered, for example, patients stay up late for a long time, lack of sleep or because the brain is in a state of long-term fatigue, unhealthy way of using the brain, nutritional imbalance, all of which can easily lead to mental unclearness, dizziness and dullness; 2. The most common cause of mental unclearness is due to Chronic ischemia and hypoxia of the brain tissue. The reason may be due to atherosclerosis, narrowing of the lumen of the blood vessels supplying the brain or high fat and high coagulation of the blood, causing slow cerebral blood flow; 3, there are also some systemic diseases, such as anemia, hypotension, cardiogenic cerebral blood supply deficiency, cervical spondylosis, can lead to the symptoms of mental unclearness.