The Brain May Start to Age at 40 Years
 (NY, Reuters Health, 6/10/04)

Dr. Bruce A. Yankner of Harvard Medical School in Boston, and associates, studied the brains of people 26 to 106 years old. The scientists found reduced activity after age 40 in the genes of the brain that are associated with various cell functions. In fact, between 40 and 70 years of age, DNA damage may accumulate and affect learning and memory, resulting in wide differences in gene activity between people of the same age. These findings suggest that the aging of the brain in some middle-aged people may proceed more slowly, so that individuals reach 'old age' at different rates.