Ellie may be a computer simulation, but she's incredibly perceptive. By reading the body language and vocal inflections of real live humans, she can engage in surprisingly meaningful exchanges, and even evoke emotional openness from her conversation partners. Her creators believe her receptivity to human emotional cues could revolutionize the field of mental health. Watching Ellie in action, it's not hard to see why.

NPR's Alix Spiegel has the details:

Under the wide screen where Ellie's image sits, there are three devices. A video camera tracks facial expressions of the person sitting opposite. A movement sensor — Microsoft Kinect — tracks the person's gestures, fidgeting and other movements. A microphone records every inflection and tone in his or her voice. The point, [explains Ellie's co-creator, USC psychologist Albert "Skip" Rizzo], is to analyze in almost microscopic detail the way people talk and move — to read their body language.

"We can look at the position of the head, the eye gaze," Rizzo says. Does the head tilt? Does it lean forward? Is it static and fixed?" In fact, Ellie tracks and analyzes around 60 different features — various body and facial movements, and different aspects of the voice.

The theory of all this is that a detailed analysis of those movements and vocal features can give us new insights into people who are struggling with emotional issues. The body, face and voice express things that words sometimes obscure.

Those familiar with ELIZA will immediately recognize Ellie as the latest in a decades-long string of chat bots designed to engage in surprisingly human interactions – including person-centered psychotherapy. What makes Ellie different is her physical manifestation, and her ability to not just mirror her conversation partner's words and body language, but analyze and react to that information in a way that encourages people to continue talking; in this sense, Ellie has better social skills than a lot of people we know.

We anxiously await the video of two Ellie bots psychoanalyzing one another.

Read more about Ellie and her creators over at NPR.