Two years ago, Alison Darcy built a robot to help out the depressed. As a clinical research psychologist at Stanford University, she knew that one powerful way to help people suffering from depression or anxiety is cognitive behavioral therapy, or C.B.T. It's a form of treatment in which a therapist teaches patients simple techniques that help them break negative patterns of thinking. C.B.T. is not difficult to learn, but it's more effective when it includes regular check-ins with a therapist — which, as Darcy knew, isn't feasible for most people. Maybe they can't afford it; maybe they're too busy; maybe they avoid treatment because it seems stigmatizing to them.
"Two-thirds of people will never get in front of a clinician," says Darcy, who talks in an exuberant flow. "And that's in the United States! The rest of the world? More than half the world doesn't even have access to basic health care. The idea of mental health care is just completely out of reach."
Darcy happened to be a former computer programmer, so she was able to dream up a very unusual solution to this problem: Woebot, a text-chatbot therapist. Working with a team of psychologists and Andrew Ng, a pioneer in artificial intelligence, Darcy wrote a set of conversational prompts that walks users through the practice of C.B.T. In a chipper style, the bot helps users challenge their "distorted thinking"; it coaxes users to describe their moods more clearly. Since Woebot is just software, it could be made freely available worldwide, and it could, in Silicon Valley terms, "scale" — or converse with thousands of people simultaneously. It could check in and nudge users with superhuman diligence; it would be available at all hours. "Woebot can be there at 2 a.m. if you're having a panic attack and no therapist can, or should be, in bed with you," Darcy says.