Age can and often does negatively impact memory capacity, but aging doesn't necessarily always affect memory. An older person with a more sedentary and isolated lifestyle will likely show poorer short-term memory retention. Happier people also have a better memory than people who are stressed or depressed. Hormones and proteins that protect and repair brain cells and stimulate neural growth decrease with age. Older people often experience decreased blood flow to the brain, which can impair memory and lead to changes in cognitive skills.