One reason Alice Flaherty pursued neurology over psychiatry is because the former, she says, is for people "who don't want to deal with the messy stuff of emotions." But messy emotions found her anyway in 1998, when she developed postpartum mania after her twin boys died during childbirth. She became hypergraphic, frenziedly writing on any surface--napkins, furniture, her skin--for four months. The same thing happened a year later, after she successfully gave birth to twin girls. Flaherty was diagnosed with bipolar disorder and turned an academic eye on her condition, penning the 2004 best-seller The Midnight Disease: The Drive to Write, Writer's Block, and the Creative Brain. She's also written a widely used neurology handbook and the children's book Luck of the Loch Ness Monster: A Tale of Picky Eating, which was made into a video.

Since her diagnosis, Flaherty has embraced emotions as a researcher, teacher, and doctor. She's currently writing a book about the biology of illness behaviors, like hypochondria and empathy. One interest is improving physicians' bedside manner. "Doctors can gain a lot of Asperger's characteristics," she says: many learn to dodge patient emotions by avoiding eye contact and using rapid, jargon-filled speech. She teaches her students at Harvard Medical School, where she's an assistant professor, to provide better care by learning how to identify and respond to patients' emotional states.

As director of Massachusetts General Hospital's fellowship program in movement disorders, she specializes in treating psychiatric and neurological diseases through deep brain stimulation, in which electrodes are implanted in the brain to alter its electrical impulses. By using handheld devices that control current flowing to their implants, patients can regulate psychiatric problems such as compulsions and motor symptoms such as tremors.

Flaherty credits her time at MIT, where she earned a PhD through the Harvard-MIT Health Sciences and Technology program, with providing the skills and mind-set that help her create lasting improvements in patients' lives. "MIT rubs off on you that you can fix things ... and make things better," she says. She wishes that other neurologists thought more like engineers.

These days, medicine largely controls her mood swings. When they do occur, she takes advantage of her illness by writing while manic and editing while depressed. She tries to instill in newly ill patients, especially college students, the message that they can be productive and successful despite having a mental illness.

In addition to writing in her spare time, Flaherty plays ice hockey on an MIT club team. She lives near Boston with her husband and 10-year-old daughters.