Alzheimer’s disease is a disease in the brain that causes brain changes that gradually get worse. In Alzheimer's disease, brain cells degenerate and die, causing a steady decline in memory and mental function. It is also the most common cause of dementia; a group of brain disorders that cause progressive loss of intellectual and social skills, severe enough to interfere with day-to-day life. This disease is developed in the brain. In Alzheimer's disease, there is an overall shrinkage of brain tissue. The grooves or furrows in the brain, called sulci , are noticeably widened and there is shrinkage of the gyri , the well-developed folds of the brain's outer layer. In addition, the ventricles, or chambers within the brain that contain cerebrospinal fluid, are noticeably enlarged. In the early stages of Alzheimer's disease, short-term memory begins to fade when the cells in the hippocampus, which is part of the limbic system, degenerate. The ability to perform routine tasks also declines. As Alzheimer's disease spreads through the cerebral cortex (the outer layer of the brain), judgment declines, emotional outbursts may occur and language is impaired. As the disease progresses, more nerve cells die, leading to changes in behavior, such as wandering and agitation. In the final stages of the disease, people may lose the ability to recognize faces and communicate; they normally cannot control bodily functions and require constant care. Scientists believe that for most