Direct brain-to-brain communication has been a long-held ambition of scientists and science fiction fans alike. Recently, University of Washington (UW) researchers brought that ambition a step closer to reality by successfully conducting a direct brain-to-brain connection between pairs of volunteers over the internet by transmitting signals from one person’s brain to another to directly govern the motions of the receiving person’s hand.

Direct brain-to-brain communication has been a long-held ambition of scientists and science fiction fans alike. Recently, University of Washington (UW) researchers brought that ambition a step closer to reality by successfully conducting a direct brain-to-brain connection between pairs of volunteers over the internet by transmitting signals from one person’s brain to another to directly govern the motions of the receiving person’s hand.

Building on initial research conducted in August 2013, where UW scientists first demonstrated direct human brain-to-brain interfacing, the researchers claim to have further developed and improved the technology and proved its worth using volunteer participants. In the latest tests, the team was able to control a subject's hand remotely by having one subject thinking about moving their hand to operate part of a video game and having these signals sent to a remote person whose hand is made to move to actually use the video game control.

"The new study brings our brain-to-brain interfacing paradigm from an initial demonstration to something that is closer to a deliverable technology," said assistant professor of psychology Andrea Stocco. "Now we have replicated our methods and know that they can work reliably with walk-in participants."

Using a combination of two kinds of non-invasive devices and software specifically configured to the task, the researchers were able to hook-up two brains in real time. In essence, one participant has an electroencephalograph wired to read specific brain activity and then send those signals via the internet to a second participant, who has a transcranial magnetic stimulation coil located above the part of the brain that controls hand movements. As such, when one person thinks about moving their hand, a signal is sent to the other person who moves their hand as if it was their thought.

The research involved six volunteers, split into three pairs. These pairs consisted of a dedicated sender and a receiver, each with designated instructions on how to participate. Each half of the pair were in separate buildings and unable to communicate with each other apart from the internet link established between their brains.

Both were seated in front of a computer game where they had to fire a cannon or rockets. However, because the senders were restricted from physically interacting with the game, they could only think about using their hand to fire their weapons. At the same time, the people acting as receivers were housed in a darkened room wearing headphones and with no vision of the computer game.

Their right hand was poised over a touchpad wired into the game and able to fire the weapon. When the brain-to-brain interface resulted in receipt of a successful signal, the receiver’s hand would be commanded to fire the weapon seen in the game on the sender’s computer screen.

Accuracy varied from 25 to 83 percent in between the pairs, but researchers claim that most of the misses were mainly due to a sender failing to execute a timely firing thought to launch a weapon, rather than any inaccuracy inherent in the system itself.

As such, the researchers are confident that this new research shows a marked improvement in brain-to-brain interfaces, as the participants in this exercise were completely unknown to each other, had no previous encounters with such technology, and – most importantly – had no idea of what to expect when hooked-up to these devices.

Unlike other Web-connected brain-to-brain interfaces that require interpretation of flashes of light, this technology may one day assist in such things as transferring motor responses and advanced capabilities to ordinary people from experienced senders.

"Imagine someone who’s a brilliant scientist but not a brilliant teacher," said co-author Chantel Prat, a faculty member at the Institute for Learning & Brain Sciences. "Complex knowledge is hard to explain – we’re limited by language."