Internet searches activate regions in the brain that control complex reasoning and decision making, the Center found in a nine-month study of 24 neurologically normal volunteers, with similar education levels, ages 55 to 76.

The test subjects showed richer sensory experience and heightened attention when conducting Internet searches, as opposed to reading book-like text on computers, said Gary Small, the Center's director, noting the brain activity was recorded in MRI results.

Not enough research yet exists to show whether Internet use can ward off dementia, The San Francisco Chronicle reported Sunday, noting Alzheimer's cases in the United States are expected to quadruple by 2050.

The Center's findings are to be published next month in the Journal of Geriatric Psychiatry.