How to Get "A Good Night's Sleep"

Sonia Ancoli-Israel specializes in sleep disorders, including sleep apnea, insomnia and sleep disturbances in the elderly. She is the author of "All I Want is a Good Night's Sleep." (Mosby-Year Book) She directs the Sleep Disorders Clinic at the Veterans Affairs Division of the San Diego Health Care System.

White noise streams are a kind of sonic wallpaper. For many, they help keep some parts of the brain distracted so that other parts may better focus on things, like writing, studying or sleeping.

Daniel Lieberman is a professor in the department of human evolutionary biology at Harvard. He says that the notion of "getting exercise" — movement just for movement's sake — is a relatively new phenomenon in human history. His new book is Exercised: Why Something We Never Evolved to Do Is Healthy and Rewarding.