Improving Memory

Car Exhaust Bad for Your Brain

I s traffc pollution clouding your brain? Harvard researchers report that a doubling of exposure to black carbon-a marker for pollution from automotive exhaust-was associated with a 30% greater chance of scoring badly on a standard test for dementia. The poorer results, plus lower scores on a composite of six other tests of cognitive function, were the equivalent of adding almost two years to subjects age. Researchers analyzed data on 680 Boston-area men, average age 71, from the VA Normative Aging Study. The in- vestigators said this was the frst study to link traffc-related air pollution and cognition in older men, and only the second study of such a relationship in older adults. Tiny particles in exhaust, researchers suggested, might lodge in the brain, or could cause cardiovascular damage that in turn affects the brain.