At our new favourite Indian buffet (Cafe Bombay) they run Bollywood videos on big screens all the time. In Bollywood, as you probably know, everybody is dancing all the time, in wonderful synchronization, like Broadway but far more. I've never been to an Indian dance club to see if people try to do that in real life, but I suspect they want to.

I started musing about a future where brain implants let you give a computer control of your limbs so you could participate in such types of dance, but I realized we might be able to do something much sooner.

Envision either a special suit or a set of cuffs placed around various parts of the arms and legs. The cuffs would be able to send stimuli to the skin, possibly by vibrating or a mild electric current, or even the poke of a small actuator.

With these cuffs, we would develop a language of dance that people could learn. Dancers have long used Dance notation to record dances and communicate them, and more sophisticated sytems are used to have computerized figures dance. (Motion capture is also used to record dances, and often to try to distill them to some form of encoding.) In this case, an association would be made between stimuli and moves. If you feel the poke on one part of your left wrist, move you left arm in a certain way, a different set of pokes commands a different move. There would no doubt have to be chords (multiple stimulators on the same cuff) to signal more complex moves.

Next, people would have to train so that they develop an intuitive response, so that as soon as they feel a stimulus, they make the move. People with even modest dance skill of course learn to make moves as they are told them or as they see them, without having to consciously think about it a great deal. The finest dancers, as we have seen, can watch a choreographer dance and duplicate the moves with great grace due to their refined skill.

I imagine people might learn this language with something like a video game. We've already seen the popularity of Dance Dance Revolution (DDR) where people learn to make simple foot moves by seeing arrows on the screen. A more advanced game would send you a stimulus and test how quickly you make the move.

The result would be to become a sort of automaton. As the system fed you a dance, you would dance it. And more to the point, if it fed a room full of people a dance, they would all dance the same dance, in superb synchronization (at least for those of lower skill.) Even without the music though normally this would all be coordinated with that. Dance partners could even be fed complimentary moves. Indeed, very complex choreographies could be devised combined with interesting music to be done at dance clubs in moves that would go way beyond techno. I can see even simple moves, getting people to raise and move hands in patterns and syncs being very interesting, and more to the point, fun to participate in.

In addition, this could be a method to train people in new and interesting dances. Once one danced a dance under remote control several times one would presumably then be able to do it without the cuffs, and perhaps more naturally. Just like learning a piece of music with the sheet music and eventually being able to take the music away.

I suspect the younger people were when they started this, the better they would be at it.

It could also have application in the professional arena, to bring a new member of a troupe up to speed, or for a dance to be communicated quickly. Even modest dancers might be able to perform a complex dance immediately. It could also possibly become a companion to Karaoke.

There are other means besides cuffs to communicate moves to people of course, including spoken commands into earphones (probably cheapest and easiest to put on) and visual commands (like DDR) into an eyeglass heads-up-display once they become cheap. The earphone approach might be good for initial experiments. One advantage of cuffs is the cuffs could contain accelerometers which track how the limb moved, and thus can confirm that the move was done correctly. This would be good in video game training mode. In fact, the cuffs could even provide feedback for the correct move, offering a stimulus if the move is off in time or position.

There have been some "use people as robots" experiments before, but let's face it, dance is more fun. And an actual Bollywood movie could come to life.