Narrator: This is Science Today. For a long time it's been known that people who are cognitively active have a lower risk of getting Alzheimer's disease. But why that happens has been poorly understood. A new study by researchers at the University of California, Berkeley, is helping to shed some light on the mystery.
Jagust: The standard explanation for this is that people who are cognitively active have sort of a more resilient, plastic brain, so when these changes of Alzheimer's disease start to occur, they can resist them.
Narrator: Using brain-imaging technologies, study leader Dr. William Jagust showed, for the first time, that cognitive activity is directly related to the buildup of amyloid protein plaques, which is a hallmark of the disease.
Jagust: We think this may be related to the finding that neural activity can actually result in amyloid release. One of the possibilities is that people who are very cognitively active throughout their lives develop an efficient brain — and so what we're seeing is some kind of improved function of the brain that results in less amyloid deposition.Narrator: For Science Today, I'm Larissa Branin.