Memory decline and depression may be strongly linked in older people, suggests the latest research. Researchers at the University of London collected data from 8,300 adults with an average age of 64. The data showed a strong correlation between those who suffered dementia and the rate at which their memory declined. "Our study shows that the relationship between depression and poor memory cuts both ways, with depressive symptoms preceding memory decline and memory decline linked to subsequent depressive symptoms," said, Dr. Dorina Cadar, senior study author. Dr. Cadar noted that depression causes "changes in brain structures, such as the hippocampus." The hippocampus is the part of the brain responsible for memory formation and retrieval. Stress and elevated cortisol levels, common in depression, can damage the hippocampus, accelerating memory decline.