Telepathy is a hallmark of both the fantasy and science fiction genres. In fantasy stories, telepathy is usually performed magically or by people with supernatural abilities. But science fiction tales take a more realistic approach where characters can communicate telepathically using some sort of technology, such as brain implants. Given how little we know about the brain and how it works, it’ll be a long time before real telepathic communication is possible. However, researchers from the University of Washington have developed a brain-to-brain interface that allows three people to play a Tetris-like game together.
The game itself is similar to Tetris, but far more simple. The only things on the screen are a block at the top and a line at the bottom. Players have to rotate the block in such a way that it will fit into a gap in the line when it falls down. This game would, of course, be extremely easy for a person to play on their own. But the players aren’t controlling the game by themselves, and instead are coordinating the gameplay with two other players through brain-to-brain interfaces. The person who actually controls the game is dubbed the “receiver,” while the other two people are the “senders.”
The senders can see both the block and the line, but can’t actually control the game. The receiver can only see the block — not the line. Each person is sitting in a separate room and can’t see or hear the others. The idea is that the senders will let the receiver know if they should or should not rotate the block. To do that, they concentrate on either a “yes” light that blinks 17 times per second, or a “no” light that blinks 15 times a second. Concentrating on one of those lights produces unique brain activity that can be picked up by a electroencephalography cap that the senders wear.
Once the senders make a decision, it is sent to the receiver using a unique device that can stimulate brain activity. If the answer was “yes” they will see bright arcs of light. If the answer is no, they won’t see anything. The receiver can then use the same method as the senders to make a decision on whether the block should be rotated. In testing, they had five groups of three players participate in 16 rounds of the game. They found that, on average, the players successfully cleared the line 13 out of those 16 times. The game itself may be simple, but this technology is a huge step forward for brain-to-brain interfaces.