From thegamereviews.com:

The development of accessible controllers isn’t a new idea. Tinkerers, generally working independently from the mainstream gaming industry have been working with video games since the days of the Atari. Ken Yankelevitz was one the earliest people working in this field. He began his work in 1981, when Atari referred him to a quadriplegic teenager who, lacking the means for conventional recreation, wanted to play video games. He would go on to do much more of this work through his company KYE, designing custom controllers based on the personal and individual needs of each client, a process which has grown increasingly complicated as games and controllers have advanced.

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