Study shows direct brain interface between humans

UW study shows direct brain interface between humans
UW students Darby Losey, left, and Jose Ceballos are positioned in two different buildings on campus as they would be during a brain-to-brain interface demonstration. The sender, left, thinks about firing a cannon at various points throughout a computer game. That signal is sent over the Web directly to the brain of the receiver, right, whose hand hits a touchpad to fire the cannon. Credit: U of Washington

Sometimes, words just complicate things. What if our brains could communicate directly with each other, bypassing the need for language?

University of Washington researchers have successfully replicated a direct brain-to-brain connection between pairs of people as part of a scientific study following the team's initial demonstration a year ago. In the newly published study, which involved six people, researchers were able to transmit the signals from one person's brain over the Internet and use these signals to control the of another person within a split second of sending that signal.

At the time of the first experiment in August 2013, the UW team was the first to demonstrate two communicating in this way. The researchers then tested their brain-to-brain interface in a more comprehensive study, published Nov. 5 in the journal PLOS ONE.

"The new study brings our brain-to-brain interfacing paradigm from an initial demonstration to something that is closer to a deliverable technology," said co-author Andrea Stocco, a research assistant professor of psychology and a researcher at UW's Institute for Learning & Brain Sciences. "Now we have replicated our methods and know that they can work reliably with walk-in participants."

Collaborator Rajesh Rao, a UW associate professor of computer science and engineering, is the lead author on this work.

The research team combined two kinds of noninvasive instruments and fine-tuned software to connect two human brains in real time. The process is fairly straightforward. One participant is hooked to an electroencephalography machine that reads brain activity and sends electrical pulses via the Web to the second participant, who is wearing a swim cap with a transcranial magnetic stimulation coil placed near the part of the brain that controls hand movements.

UW study shows direct brain interface between humans
A transcranial magnetic stimulation coil is placed over the part of the brain that controls the receiver's right hand movements. Credit: U of Washington

Using this setup, one person can send a command to move the hand of the other by simply thinking about that hand movement.

The UW study involved three pairs of participants. Each pair included a sender and a receiver with different roles and constraints. They sat in separate buildings on campus about a half mile apart and were unable to interact with each other in any way – except for the link between their brains.

Each sender was in front of a computer game in which he or she had to defend a city by firing a cannon and intercepting rockets launched by a pirate ship. But because the senders could not physically interact with the game, the only way they could defend the city was by thinking about moving their hand to fire the cannon.

Across campus, each receiver sat wearing headphones in a dark room – with no ability to see the computer game – with the right hand positioned over the only touchpad that could actually fire the cannon. If the brain-to-brain interface was successful, the receiver's hand would twitch, pressing the touchpad and firing the cannon that was displayed on the sender's computer screen across campus.

Researchers found that accuracy varied among the pairs, ranging from 25 to 83 percent. Misses mostly were due to a sender failing to accurately execute the thought to send the "fire" command. The researchers also were able to quantify the exact amount of information that was transferred between the two brains.

Another research team from the company Starlab in Barcelona, Spain, recently published results in the same journal showing direct communication between two human brains, but that study only tested one sender brain instead of different pairs of study participants and was conducted offline instead of in real time over the Web.

UW study shows direct brain interface between humans
The sender is hooked to an electroencephalography machine that reads brain activity. A computer processes the brain signals and sends electrical pulses via the Web to the receiver across campus. Credit: U of Washington

Now, with a new $1 million grant from the W.M. Keck Foundation, the UW research team is taking the work a step further in an attempt to decode and transmit more complex brain processes.

With the new funding, the research team will expand the types of information that can be transferred from brain to brain, including more complex visual and psychological phenomena such as concepts, thoughts and rules.

They're also exploring how to influence brain waves that correspond with alertness or sleepiness. Eventually, for example, the brain of a sleepy airplane pilot dozing off at the controls could stimulate the copilot's brain to become more alert.

The project could also eventually lead to "brain tutoring," in which knowledge is transferred directly from the of a teacher to a student.

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

Explore further

Researcher controls colleague's motions in first human brain-to-brain interface (w/ Video)

More information: PLOS ONE:
Journal information: PLoS ONE

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Nov 05, 2014
If the brain-to-brain interface was successful, the receiver's hand would twitch, pressing the touchpad and firing the cannon that was displayed on the sender's computer screen across campus.

In essence, the "brain-to-brain" interface causes a small electric shock in the reciever's motor cortex that causes an involuntary hand twitch. This is not actually brain-to-brain communication in the sense that the other person recieves your intent and chooses to act accordingly, but simply remote control of the other person.

It wouldn't be any different if you used their hand to tap the clicker by electric shocks direclty into the muscles.

Nov 06, 2014
Pulling on the electric wires between them would also help to communicate ;)

Nov 06, 2014
For a moment there, while reading the title and teaser, I was really excited. I've thought that brain-to-brain signals might be the next neuroscience revolution ever since learning about brain-computer interfaces from the now legendary Matt Nagle case.

But this particular experiment setup is actually rather useless. On the sender side, it is just a rudimentary BCI, on the receiver side, as noted by Eikka above, it is closer to computer-muscule interface and not computer-brain interface in any useful way.

Nov 06, 2014
With enough advancements in brain-computer and computer-brain interfaces, their combination would allow interesting new forms of communications.

At first they will be centered around current spoken or written languages but may eventually lead to development of new "languages" that are more suitable for computer-assisted mediation, much more accurate and efficient, eliminating mishearing and ambiguities, and likely increasing the speed at which we communicate. They may also be better at expressing or in some cases literally transmitting senses, emotions, intents, memories, sounds and visuals, ideas... thoughts.

Language and communication are key factors to how we learn to think at a young age. So developments in this area might reshape the limits of human intelligence in the generations that follow, and that is just from the improved communication efficiency, before even considering actual brain augmentation that might become possible with increased understanding of our brain

Nov 06, 2014
There is also some potential in raw brain-(computer)-brain interfaces that do not even try to decode, analyze or understand the signal, only transmit it as-is.

The brain's plasticity and ability to adapt and learn is quite fascinating, especially at a young age. I will not be surprised if two brains that are sufficiently connected with each other could learn to use the connection all on their own.

With a large enough connection from a young enough age it even would not surprise me if two physical brains developed as a single common consciousness, perhaps surpassing regular human intelligence.

That will require invasive, implant-based, likely even single neuron level connections, lasting a long period of time, and is more likely to be successful with younger and still developing brains, so it has not only huge technological but also ethical challenges. It is not likely to get actually tested any time soon, if ever.

Nov 06, 2014
After thinking about it a bit, this could work if the 2 people worked through trial and error to develop a means of signalling each other to transfer information. However, transferring information between two people not trained to communicate with each other via this method is unlikely to work. Assuming that all of the electrical activity in the brain is encoded in the electrical signals in the scalp, you would need a reliable algorithm to decode that into a 3D map that gives the required signal strength as a function of position in the brain. Then you would need to generate an electromagnetic field that could reproduce that 3D signal map in the recipient's brain. However, assuming that each individual's neural interconnections are unique, it seems unlikely to me that the recipient will interpret the map in the same way as the sender. It's more likely to me that they will need to train with each other to develop a common means of signalling through trial and error.

Nov 07, 2014
the novelty/hype ratio very much in the style of Rao :)

as the team sizes increase exponentially, with projected average of 18.7 coauthors in physical sciences expected by 2040, (http://www.nature...0.html), the pressure to communicate swiftly will soon create a rush to develop battery-less implants allowing not only non-vocal, but even non-verbal exchanges of thoughts. one can even imagine sort of "cluster thinking" as a replacement of traditional discussions or lessons. the brain is so plastic that such extra communication channel will quickly be adopted as one of one's own senses.

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