The Choscillator is a game made from a hacked Mindflex toy and a welded chair. The game participant sits in the chair in front of a computer monitor and adorns the Mindflex headgear which feeds brainwave data into the game.
The gameplay is an endless oscillation driven by human and computer feedback. The human alternates between relaxed and focused states as requested by the computer, switching when the human's present state matches the computer's requested state for a sufficient amount of time.
I ask the participant to focus and concentrate to make the white box larger (see animation below), and relax and breathe to make the black box smaller. The animation continues smoothly if the participant complies; otherwise, it halts.
Download: Game source code. Contact me for a description of the algorithm.
Photo credit: Derek Means
Photo credit: Chris Jordan