Small voltage changes on the scalp are due to electrical currents occurring in the brain. Activity in various parts of the brain is associated with particular processes such as vision, motion or language recognition. The idea of using the external voltage to control prosthetic devices has been hovering around for the last forty years or thereabouts. A brain-computer interface is required and the possibilities are much more exciting today than when the concept was first proposed.
The idea of expanding the brain-computer interface to improve the performance of normal healthy people has been raised by Wang and Jung of U Cal. San Diego (1) who couple it with an elementary form of crowd wisdom. A small group of wired individuals were given visual cues to do things with their fingers – on a touch screen of course. At the same time the voltages over their post-parietal cortex, was monitored. This is the region of the brain where we try and integrate what we see with what we are going to move. These signals were used to predict which of three targets the participants were supposed to poke.
The response time of the participants was measured and this provides a baseline for the big experiment – the collaborative one in which the feedback from the group could predict the decision of which target should be poked.
The average time it took for an individual to see the cues and then hit the target was a little under half a second with an average hit accuracy of 65%. Now, when the brain outputs were averaged, that is the target was voted on, the correct target was identified in 45% of the response time with an accuracy of 70%. That means that an artificial finger could have been used to hit the target faster and with a higher accuracy that a real finger.
All of this sounds very geeky, but poking at a target on a touch screen is not the final objective. With the advances in wireless computing and miniaturization, one can imagine a busload of backseat drivers taking us at faster rate through the busy traffic, but more safely and with never a bad word being shouted or a finger being raised in admonition. This is a close to telepathy that most of us will get.
