Valve has a surprisingly varied staff roster. Mike Ambinder is the company's very own experimental psychologist and he's been outlining some of Valve's work with biofeedback technology, including eye-motion controls for Portal 2 and perspiration-based gaming adjustments on Left 4 Dead. Mentioning these developments at the NeuroGaming Conference last week, Ambinder notes that both are still at an experimental stage, but that "there is potential on both sides of the equation, both for using physiological signals to quantify an emotion [and] what you can do when you incorporate physiological signals into the gameplay itself."
In Left 4 Dead, test subjects had their sweat monitored, with values assigned to how much they were responding to the action. This data was fed back into the game, where designers attempted to modify (and improve) the experience. In a test where players had four minutes to shoot 100 enemies, calmer participants would progress normally, but if they got nervous, the game would speed up and they would have less time to shoot. When it came to the eye-tracking iteration of Portal 2, the new controls apparently worked well, but also necessitated separating aiming and viewpoint to ensure it worked. With Valve already involving itself in wearable computing, it should make both notions easier to accomplish if it decides to bring either experiment to fans. Venture Beat managed to record Ambinder's opening address at the conference -- we've added it after the break.