Play video game with friends using only your minds

A recent study updated the telepathic communication leading to a method that allows three people to work together to solve a problem using only their minds.

According to the study published in the journal of Scientific Reports, In BrainNet, a platform used for research, three people play a Tetris-like game using a brain-to-brain interface. This is the first demonstration of two things: a brain-to-brain network of more than two people, and a person being able to both receive and send information to others using only their brain.

"Humans are social beings who communicate with each other to cooperate and solve problems that none of us can solve on our own. We wanted to know if a group of people could collaborate using only their brains. That's how we came up with the idea of BrainNet: where two people help a third person solve a task," said corresponding author Rajesh Rao.

As in Tetris, the game shows a block at the top of the screen and a line that needs to be completed at the bottom. Two people, the Senders, can see both the block and the line but can't control the game. The third person, the Receiver, can see only the block but can tell the game whether to rotate the block to successfully complete the line.

Each Sender decides whether the block needs to be rotated and then passes that information from their brain, through the internet and to the brain of the Receiver. Then the Receiver processes that information and sends a command to rotate or not rotate the block to the game directly from their brain, hopefully completing and clearing the line.

The team asked five groups of participants to play 16 rounds of the game. For each group, all three participants were in different rooms and couldn't see, hear or speak to one another.

The Senders each could see the game displayed on a computer screen. The screen also showed the word "Yes" on one side and the word "No" on the other side. Beneath the "Yes" option, an LED flashed 17 times per second. Beneath the "No" option, an LED flashed 15 times a second.

"Once the Sender makes a decision about whether to rotate the block, they send 'Yes' or 'No' to the Receiver's brain by concentrating on the corresponding light," said first author Linxing Preston Jiang.

"To deliver the message to the Receiver, we used a cable that ends with a wand that looks like a tiny racket behind the Receiver's head. This coil stimulates the part of the brain that translates signals from the eyes. We essentially 'trick' the neurons in the back of the brain to spread around the message that they have received signals from the eyes. Then participants have the sensation that bright arcs or objects suddenly appear in front of their eyes," said co-author Andrea Stocco.

If the answer was, "Yes, rotate the block," then the Receiver would see the bright flash. If the answer was "No," then the Receiver wouldn't see anything. The Receiver received input from both Senders before making a decision about whether to rotate the block. Because the Receiver also wore an electroencephalography cap, they used the same method as the Senders to select yes or no.

The Senders got a chance to review the Receiver's decision and send corrections if they disagreed. Then, once the Receiver sent a second decision, everyone in the group found out if they cleared the line. On average, each group successfully cleared the line 81% of the time, or for 13 out of 16 trials.

The team hopes that these results pave the way for future brain-to-brain interfaces that allow people to collaborate to solve tough problems that one brain alone couldn't solve.

"But for now, this is just a baby step. Our equipment is still expensive and very bulky and the task is a game. We're in the 'Kitty Hawk' days of brain interface technologies: We're just getting off the ground," Rao said.