Imagine a future where you could transmit a unique feeling, a hard-to-translate thought process, or precise motor movements via a neural pattern from your brain to someone else’s brain, sharing what can’t otherwise be easily communicated. This is the goal of new research conducted at the University of Washington (UW).
In the UW experiment, published in PLOS ONE, subjects played a 20 Questions–style game through a direct brain-to-brain connection, and accurately guessed what object was on the other person’s mind 72 percent of the time.
“We wanted to show that this brain-to-brain interface can be used to do something highly interactive and collaborative,” lead author Andrea Stocco, an assistant professor of psychology and researcher at UW’s Institute for Learning and Brain Sciences, tells mental_floss,
The function of the experiment is conceptually simple, Stocco says. Two people sit apart in different buildings. One, the respondent, is wearing a cap connected to electroencephalography machine (EEG) that records electrical brain activity. A magnetic coil is placed behind the head of the other participant, the inquirer. The coil delivers “transcranial magnetic stimulation.” The respondent is given an object to think of, much like in the game Twenty Questions. Then the inquirer chooses questions to send to the respondent via the Internet. The respondent answers the questions using only their brainwaves, by thinking the answer “yes” or “no.”
“Yes and no buttons are designed with lights around them to generate different visual signals, which we can pick up by analyzing brain waves in the visual part of the brain,” Stocco says.
These yes and no answers send a signal to the inquirer and activate the magnetic coil connected to the inquirer’s cap. Only a “yes” answer generates enough stimuli to activate the visual cortex, thus allowing the inquirer to see a subtle flash of light, or “phosphene

We have a lot of control conditions to limit chance and use complicated math to measure the results," Stocco says. “After, we measured performance and found the rate of success was much higher than what would happen by chance."
Participants were able to guess the correct object 72 percent of the time, compared with just 18 percent in the control rounds.
This study evolved from research that has been ongoing since 2011 between Stocco, Rajesh Rao, and Chantel Prat, fellow UW professors. The researchers received a $1 million grant from the W.M. Keck Foundation to pursue these kinds of brain-to-brain interfaces.
Stocco hopes that this technology could one day be used to “transfer more complicated things” between brains, like emotions but also brain states, such as signals from an alert person to a sleepy one, and other forms of nonverbal communication. “There is an entire realm of things we have a hard time communicating,” Stocco says. He gives the example of one day taking an ADHD student who struggles to focus, and linking them up to the brain of a “neurotypical” person who has good focus. In theory, the calm neural pattern of the neurotypical student could perhaps be transmitted to the ADHD student to help him focus.
“Person-to-person transfer is a long way off, but you would be amazed by the progress,” he says, pointing out that wireless EEG headsets are already available for use in gaming. “We can record brain activity, but no one has been able to transfer it until now. In all kinds of different experiences, the neurosignals recorded could become a shortcut.”