How good is your memory? Memory changes as you age, but it can be nerve-wracking when it feels like your memory is starting to go downhill. Take this test to find out how strong your memory is.

There are strategies for coping with such loss—adopting memory aids such as calendars and reminder notes, for example, or routinizing the placement of objects at risk of getting lost.

Last month two research teams reported success at using electrical signals, carried into the brain via implanted wires, to boost memory in small groups of test patients. “It’s a major ...