Begley graduated from Yale University in 1977  and then began working at Newsweek, where she has spent most of her career. From 2002 to 2007, she wrote the "Science Journal" column in the Wall Street Journal. In 2007, Begley's Newsweek cover-story on climate change focused on what she called the "denial machine." Her article received widespread, "sometimes-furious" criticism. She is the author of Train Your Mind, Change Your Brain: How a New Science Reveals Our Extraordinary Potential to Transform Ourselves, as well as the co-author of The Mind and the Brain: Neuroplasticity and the Power of Mental Force, along with psychiatrist Jeffrey M. Schwartz.