Gary Small, professor of psychiatry and aging and director of the UCLA Longevity Center, will visit Riderwood retirement community on Jan. 10 at 1 p.m. for a free one-hour presentation on his book The Alzheimer’s Prevention Program: Keep You Brain Healthy for the Rest of Your Life. It will be held in Riderwood’s Montgomery Hall. To reserve a free ticket, call 301-572-8395. Books can be purchased with cash, check or credit card. Refreshments will be served after the presentation. Riderwood is at 3140 Gracefield Road in Silver Spring.