"Gordon Pask developed musical cybernetic systems that count as early
cyborg hybrids. His 1953 Musicolour machine accompanied musical
performers. As the performer or group played, Musicolour responded with
lights and movement to the music would change, creating a sort of
hypnotic effect for those who played with it. But if the performer
became too repetitive and did not engage the machine enough, Musicolour
would grow bored and stop responding—the first cybernetic art system to
do so. [4] Pask also noted that while people trained the machine, it
trained them back, creating a feedback loop in which performers felt
like the machine was an extension of their minds and bodies.[5]"
[5] Ibid., 85.
Has anyone played with http://brainpaint.com/ ? Generates fractals from brainwaves for "therapy".