Recovery Michigan

We've known for quite a while that some people seem to escape cognitive decline well into their nineties and beyond. Intriguingly, the brains of these sharp older people often reveal the extensive abnormalities like the "plaques" and "tangles" seen in people with Alzheimer's. We think it's because they've built what neuroscientists call "cognitive reserve." Most systems in our bodies can sustain some level of damage before they start to malfunction, and the brain is no exception. We build cognitive reserve -- extra neurons and the connections between them -- by resisting habit and inertia and continuing to learn new things. But how does this forestall or prevent memory loss and other diseases associated with old age?

When scientists at Chicago's Rush University Medical Center in Chicago dug deeper, they uncovered another, overarching factor. They examined the brain tissues of 246 people who died during a long-term study of more than 1,400 older men and women. The autopsy results, reported inArchives of General Psychiatry, were striking. People who exhibited very different levels of cognitive decline often showed similar levels of damage from Alzheimer's. The brains that functioned better, it turned out, belonged to people who had indicated more purpose in life over the course of the study.

In other words, having a goal in life actually affects cellular activity in the brain. Plaques and tangles still form, but having a goal seems to increase the brain's protective reserve. Not only that, the stronger the purpose, the more it adds to the reserve. The results held up even after the researchers controlled for differences in exercise levels, education, and other factors. Other studies link a sense of purpose not only to slower rates of cognitive decline but to lower rates of disability and death.