SAINT: Hope for new treatment of depression

In her garden outside San Francisco, Deirdre Lehman tries to keep her demons at bay. For most of her life, medication and therapy have helped keep her depression under control.

"I'm technically bi-polar," she said. "You can have episodes of the quiet time where the disease doesn't appear."

But when it does appear, for Lehman it's like tumbling head-first into depression's deepest abyss.