Brain cells are irreversible, and once they die, they cannot regenerate. If brain atrophy occurs, it means that some brain cells have necrosed, and complete recovery is impossible. However, some patients with brain atrophy have no clinical symptoms because the brain's compensatory function is relatively strong. The usual causes of brain atrophy include the following. Firstly, Alzheimer's disease, which is the most common cause of dementia. Patients exhibit cortical brain atrophy, especially in areas such as the temporal lobes, frontal lobes, and hippocampus. Treatment is primarily symptomatic, and curing the disease is very difficult. Another cause is cerebrovascular disease. Long-term cerebral ischemia and arterial stenosis can also lead to brain atrophy. It is crucial to actively improve circulation and use anti-atherosclerosis medications for treatment. Additionally, some toxic encephalopathies, leukoencephalopathies, and drug toxicities can also cause brain atrophy. (Specific medications should be used under the guidance of a doctor.)