Researchers at the University of Washington just demonstrated that two people could work together telepathically to play a video game.

One player could control another player's hand with his thoughts

How did that work? One of the subjects could see the game, but had no controller. His partner had a controller, but couldn't see the game. By using electrodes and electromagnets, the researchers created a way to allow the first person to control the second person's controller hand just by thinking about it.

It's pretty impressive — although the experiment doesn't quite mean we're on the cusp of being able to read each other's minds. For one, telepathically controlling hand twitches isn't quite the same as sharing ideas, thoughts, or dreams.

This telepathy research could end up being largely useless — or it could be what everyone ends up doing in a few decades. Here's what you need to know about recent advances in this field:

(University of Washington)

Two people are cooperating to play a game that involves firing a canon at targets. Person A can see the game, but has no controller. Person B has a controller, but can't see the game. So Person A needs some way to tell Person B how to play.

Here's how: When Person A wanted to make a move in the game, he simply thought about moving his hand. His brain signals were picked up by a cap of electrodes on his head and sent off to Person B — who was about half a mile away. There, an electromagnet beamed signals into the area of Person B's brain that controls hand movement. This stimulation automatically made Person B's hand move, touching a touchpad that controlled the game.

All in all, the communication took a split second. Participants successfully clicked when they were supposed to about 25 to 83 percent of the time, depending on the pair of people involved.

You've got brain-mail. This person is receiving a message as the experience of a flashing light. (Grau, C., et al. PLOS ONE, August 2014)

The University of Washington research group first demonstrated this electrode/electromagnet setup in a pilot study they discussed online in 2013, though this is the first time their work has been published (it's in the journal PLOS ONE).

But this isn't the first telepathy experiment to be published. In August 2014, an international group led by Starlab Barcelona researchers in Spain used similar technology to have someone send a one-word email to someone else. They called it the "realization of the first human brain-to-brain interface."

But the process of sending that one-word e-mail was extremely complicated, not very practical, and far more time-consuming than playing video games. It involved translating a message into a binary code of "0"s and "1"s. The sender imagined moving his feet for 0s and hands for 1s. And then the receiver was hooked up to a device that stimulated his brain to create the perception of flashes of light, which was then translated back into 0s and 1s.

All in all, this method of communication had a speed of 2 bits per minute — roughly one millionth the average internet speed in the US. That meant it took roughly 70 minutes just for one person to say "hola" or "ciao" to another. And, not surprisingly, the experiment wasn't perfect. The error rate ranged from 1 to 15 percent.

(Shutterstock)

One of the things that the researchers of the telepathic video-game study were interested in was nonverbal communication. In many ways, telepathy might be most useful here — because it's currently quite difficult to convey information about things like fine motor control. As they state in their paper:

A great deal of the information that is available to our brain is not introspectively available to our consciousness, and thus cannot be voluntarily put in linguistic form. For instance, knowledge about one's own fine motor control is completely opaque to the subject, and thus cannot be verbalized. As a consequence, a trained surgeon or a skilled violinist cannot simply "tell" a novice how to exactly position and move the fingers during the execution of critical hand movements. But even knowledge that is introspectively available can be difficult to verbalize. Brilliant teachers may struggle to express abstract scientific concepts in language, and everyone is familiar with the difficulty of putting one's own feelings into words.

Given how terribly long the other group's verbal telepathy experiment took, this definitely seems worth considering. After all, we already have an easy time conveying language in real time — through text messaging and email. Telepathy isn't needed as much here.

But telepathy might be far more useful, if it indeed does ever become useful, for communicating difficult-to-describe things, like emotions or motor skills.

The Emotiv EPOC EEG headset is commercially available and safe to use for both research and recreation. (Emotiv)

One thing to consider about these experiments is that they've been using off-the-shelf equipment that requires no surgery.

The brain-reading part generally consists of putting a little cap of electrodes on someone's head. It's temporary. And it's painless. The caps are widely available for purchase. Some of them are even wireless. They read the person's brainwaves through a technique called electroencephalography (or EEG) that's frequently used in medicine. Some are even available for recreational use, like the Emotiv headset above that some use for gaming.

And receiving the telepathic message has generally involved a technique called transcranial magnetic stimulation (TMS). Basically, it's an electromagnet that a researcher places in a given location outside the participant's head to stimulate brain activity in given brain area. TMS has been an active area of research recently, such as this experiment that used it to make people's memories stronger.

Some TMS devices have been FDA-approved for certain types of depression and migraine, but that does not mean that it's safe to play around with TMS devices or other forms of brain stimulation at home for rogue telepathic experiments. No one yet knows what the long-term consequences of telepathic brain-stimulation might be.

(Shutterstock)

Sometimes it's difficult to see how something using two sets of crazy-weird electronic headgear to produce one word or a few little computer clicks could ever become something useful. But it's not crazy to think that this could someday become more practical.

This kind of research is mostly a demonstration that the concept works. In the future, both the technology and the users could get better at sending messages.

For example, other researchers have used a different type of brain-reading technology, fMRI, to guess what shapes people are looking at or what type of object they were dreaming of — a building, a car, a book, et cetera. Another study used electrodes implanted within the skull to get one rat to tell another rat what lever to press for a reward. These both required far more involved and less practical technology.

But these types of brain-interfacing tech have been getting more sensitive, smaller, smarter, and more portable over time. And they'll probably continue to do so, whether you think telepathy is a good idea or not. There will, of course, be limits to what these devices could do, but we really have no idea what they are yet.

Additionally, people could meet the technology halfway, learning how to better control their thought output and how to interpret artificial electromagnetic inputs. The mind can be an astonishingly flexible tool.

Nothing's for certain. These techniques for communicating might never become useful. Or one day we might find it more handy than anything we have today. For now, these are just very early steps.

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