Tag Archives: Biomedical/Bionics

Mind Meld: Tetris Players Electronically Connect Their Brains

Post Syndicated from Emily Waltz original https://spectrum.ieee.org/the-human-os/biomedical/bionics/video-game-players-electronically-connect-their-brains

Humans collaborate using brain-to-brain communication to play video game

Have you ever felt a strong emotion, such as elation from taking in a scenic view, and wanted to share it with the people around you? Not “share” as in tell them about it or post it on social media, but actually share it—like beam the feeling from your brain into theirs?  

Researchers at the University of Washington in Seattle say they would like to give humans that kind of brain-to-brain interaction, and have demonstrated a baby step toward that goal. In a set of experiments described in the journal Scientific Reports, the researchers enabled small groups of people to communicate collaboratively using only their minds.

In the experiments, participants played a Tetris-like video game. They worked in groups of three to decide whether to rotate a digital shape as it fell toward rows of blocks at the bottom of the screen. 

The participants could not see, hear, or communicate with each other in any way other than through thinking. Their thoughts—electrical signals in the brain—were read using electroencephalography (EEG) and delivered using transcranial magnetic stimulation (TMS).

The messages sent between participants’ brains were limited to “yes” and “no”. But the researchers who developed the system hope to expand upon it to enable the sharing of more complex information or even emotions. “Imagine if you could make a person feel something,” says Andrea Stocco, an assistant professor at the University of Washington, who collaborated on the experiments.

We already try to elicit emotions from each other—to varying degrees of success—using touch, words, pictures and drugs. And brain stimulation techniques such as TMS have for more than a decade been used to treat psychiatric disorders such as depression. Sharing emotions using brain-to-brain interaction is an extension of these existing practices, Stocco says. “It might sound creepy, but it’s important,” he says.

Stocco’s experiments with the technology, called brain-to-brain interface, or BBI, are the first demonstration of BBI between more than two people, he and his colleagues say. 

To be accurate, the technology should probably be called brain-to-computer-to-computer-to-brain interface. The brain signals of one person are recorded with EEG and decoded for their meaning (computer number one). The message is then re-coded and sent to a TMS device (computer number two), which delivers electrical stimulation to the brain of the recipient.

In Stocco’s experiments, this chain of communication has to happen in the amount of time it takes a Tetris-style block to drop (about 30 seconds—it’s slow Tetris). Participants work in groups of three: two senders and one receiver. The senders watch the video game and each decide whether to rotate the block or not. Then they send their yes or no decision to the receiver, who sits in a different room, and is charged with taking action to rotate the block or not, based on the senders’ messages. (Receivers can only see half the game—the piece that is falling—and not the rows of blocks into which the piece is supposed to fit, so they depend on the senders’ advice.) 

If senders want to rotate the block, they focus their attention on an area of their screen that says “yes” with an LED flashing beneath it at 17 hertz. If they do not want to rotate it, they focus their attention on area of the screen that says “no” with an LED flashing beneath it at 15 hertz. 

The difference in brain activity caused by looking at these two different rates of flashing light is fairly easy to detect with EEG, says Stocco. A computer then evaluates the brainwave patterns, determines if they corresponded with yes or no, and sends that information to the third person in the group (the receiver). 

The receiver wears a TMS device that induces gentle, electrical stimulation in the brain non-invasively. If the message from a sender is “yes” the TMS device stimulates the receiver’s brain in a way that produces some kind of visual cue, such as a flash of color. If the message is no, the receiver gets no visual cue. Messages to the receiver from the two senders arrived one after the other, in the same order each time.

To make things interesting, the researchers asked one of the two senders to frequently transmit the wrong answer. All the receivers noticed the pattern of bad advice, and chose to listen to the more accurate sender. 

Compared with the complexity of human thought, this binary form of brain-to-brain communication is just one step toward something that might be useful outside the lab. No emotions were shared between participants, aside from perhaps a little nostalgia among the participants who grew up with the real Tetris. 

To reach a higher level of sophistication in brain-to-brain communication, researchers will likely need equipment that can read brain activity with more spatial resolution than EEG, and can stimulate with more specificity than TMS. For this, some BBI researchers are turning to fMRI and ultrasound, Stocco says.

BBI work is slow going. Stocco and his University of Washington colleague Rajesh Rao first demonstrated a form of BBI in 2013. Other groups followed on shortly after. Now, six years later, researchers working on the technology are only inches from where they started. “There are maybe four or five groups working on this globally, so we get maybe one paper a year,” says Stocco. 

DARPA Funds Ambitious Brain-Machine Interface Program

Post Syndicated from Megan Scudellari original https://spectrum.ieee.org/the-human-os/biomedical/bionics/darpa-funds-ambitious-neurotech-program

The N3 program aims to develop wearable devices that let soldiers to communicate directly with machines.

DARPA’s Next-Generation Nonsurgical Neurotechnology (N3) program has awarded funding to six groups attempting to build brain-machine interfaces that match the performance of implanted electrodes but with no surgery whatsoever.

By simply popping on a helmet or headset, soldiers could conceivably command control centers without touching a keyboard; fly drones intuitively with a thought; even feel intrusions into a secure network. While the tech sounds futuristic, DARPA wants to get it done in four years.

“It’s an aggressive timeline,” says Krishnan Thyagarajan, a research scientist at PARC and principal investigator of one of the N3-funded projects. “But I think the idea of any such program is to really challenge the community to push the limits and accelerate things which are already brewing. Yes, it’s challenging, but it’s not impossible.”

The N3 program fits right into DARPA’s high-risk, high-reward biomedical tech portfolio, including programs in electric medicine, brain implants and electrical brain training. And the U.S. defense R&D agency is throwing big money at the program: Though a DARPA spokesperson declined to comment on the amount of funding, two of the winning teams are reporting eye-popping grants of $19.48 million and $18 million.

Plenty of noninvasive neurotechnologies already exist, but not at the resolution necessary to yield high-performance wearable devices for national security applications, says N3 program manager Al Emondi of DARPA’s Biological Technologies Office.

Following a call for applications back in March, a review panel narrowed the pool to six teams across industry and academia, Emondi told IEEE Spectrum. The teams are experimenting with different combinations of magnetic fields, electric fields, acoustic fields (ultrasound) and light. “You can combine all these approaches in different, unique and novel ways,” says Emondi. What the program hopes to discover, he adds, is which combinations can record brain activity and communicate back to the brain with the greatest speed and resolution.

Specifically, the program is seeking technologies that can read and write to brain cells in just 50 milliseconds round-trip, and can interact with at least 16 locations in the brain at a resolution of 1 cubic millimeter (a space that encompasses thousands of neurons).

The four-year N3 program will consist of three phases, says Emondi. In the current phase 1, teams have one year to demonstrate the ability to read (record) and write to (stimulate) brain tissue through the skull. Teams that succeed will move to phase 2. Over the ensuing 18 months, those groups will have to develop working devices and test them on living animals. Any group left standing will proceed to phase 3—testing their device on humans.

Four of teams are developing totally noninvasive technologies. A team from Carnegie Mellon University, for example, is planning to use ultrasound waves to guide light into and out of the brain to detect neural activity. They plan to use  interfering electrical fields to write to specific neurons.

The three other teams proposing non-invasive techniques include Johns Hopkins University’s Applied Physics Laboratory, Thyagarajan’s team at PARC, and a team from Teledyne Technologies, a California-based industrial company.

The two remaining teams are developing what DARPA calls “minutely invasive” technologies which, as we described in September, require no incisions or surgery but may involve technology that is swallowed, sniffed, injected or absorbed into the human body in some way.

Rice University, for example, is developing a system that requires exposing neurons to a viral vector to deliver instructions for synthetic proteins that indicate when a neuron is active. Ohio-based technology company Battelle is developing a brain-machine interface that relies on magnetoelectric nanoparticles injected into the brain.

“This is uncharted territory for DARPA, and the next step in brain-machine interfaces,” says Emondi. “If we’re successful in some of these technologies…that’s a whole new ecosystem that doesn’t exist right now.”