MRIs are one of the ways researchers have mapped brain activity. (Somos/Veer/Jupiter Images)

Internet satellites, virtual reality, even real working AI: It all pales in comparison to the future that Facebook chief executive Mark Zuckerberg has in mind.

In a Q&A session with site users on Tuesday, the 31-year-old said he envisions a world where people — presumably Facebook users — don’t need these types of communication intermediaries. Instead, they’ll communicate brain-to-brain, using telepathy.

“One day, I believe we’ll be able to send full rich thoughts to each other directly using technology,” Zuckerberg wrote in response to a question about what’s next for Facebook. “You’ll just be able to think of something and your friends will immediately be able to experience it too.”

But hold up: Is that even possible? And is that something anyone actually wants?

TL;DR: Theoretically, yes; and, er — maybe not.

How to read a mind

To understand how Zuckerberg’s vision would theoretically work, you have to understand how the brain works, too.

In a nutshell, your nervous system is composed of cells called neurons, which communicate with each other using chemical signals called neurotransmitters. When a neuron receives one of these signals, it generates a tiny electrical spike. And because millions of these signals are required for everything your brain does — clicking your mouse, reading this text, remembering breakfast, you name it — your brain is basically sending off pinpricks of electrical energy all the time.

The cool thing about this, of course, is that scientists can measure and map this electrical activity using existing technologies like EEG and fMRI machines. And once they have enough maps, they can begin to read them — a point that neuroscientists and researchers are just now approaching.

Videos that were shown to participants in a UC Berkeley experiment (left) and videos that were reconstructed from their brain activity as they watched (right).  (UC Berkeley via YouTube)

At the University of California at Berkeley, a team of cognitive scientists have managed to reconstruct clips of movies their subjects were watching, based solely on measurements of their brainwaves. “You could not see the close-up details,” wrote the theoretical physicist Michio Kaku after watching one of the “movies,” “[but] you could clearly identify the kind of object you were seeing.”

How to send a thought

This is all well and good and interesting, of course, but the technology Zuckerberg envisions is a two-way street: How could we not only “read” a mind but also get that pattern of electrical signals into someone else’s head?

There are invasive options; i.e., implanting some kind of device in your brain. In 2013, scientists at Duke University implanted two lab rats with microelectrode arrays and taught one of the rats to press one of two levers. Afterwards, the second rat, who had not been trained, also seemed to know which level to push: It had received neural signals from the first rat, via the implant.

Recently, researchers have also had some luck with a noninvasive technique called transcranial magnetic stimulation, or TMS. When you put on a TMS headset it generates a magnetic field over your scalp, which can be used to activate neural pathways. Last fall, test subjects in India were able to use TMS  to “think” the words “hola” and “ciao” to test subjects in France; the process was painfully slow, however, and the words weren’t sent in their entirety — they had to be encoded as binary digits, uploaded to the Internet, sent, downloaded and then decoded as flashes of light. (WHEW.)

An overview of the brain-to-brain (B2B) communication system used by researchers to send the words “ciao” and “hello.” It’s really complicated. (Grau et al/PLOS One)

This is, while promising, a really clunky system. It’s unsophisticated (no one has yet “sent” an actual emotion or idea), it’s inexact (the rat still chose the wrong lever sometimes), and it’s slower than virtually every other form of modern communication, save perhaps snail mail. These experiments also required access to some very expensive, sophisticated equipment. Even if you wanted to, you could not try this at home.

“‘Telepathy’ technology remains so crude that it’s unlikely to have any practical impact,” wrote Mark Harris at the MIT Technology Review.

That said, these are only the very earliest days of telepathy research, and new developments are in the works. Among other things, researchers are looking into handheld, cellphone-sized MRI machines that would make it easier and cheaper to capture your own brain activity. And the Army is developing a telepathy helmet, almost like a VR headset, that would condense and simplify all this electrical signal-sending — although that, experts say, is still decades away.

Where Facebook fits in

Is Facebook currently developing any technology in this vein? A spokesperson for the company did not immediately respond to The Washington Post’s request for comment, though Facebook’s Research division — the arm of the company that studies machine learning, AI and virtual reality — has not published any work on brain-to-brain communication and does not appear to employ any researchers in the field.

But even if Facebook isn’t leading the charge toward telepathy — a worrying concept, in itself, given the site’s past indiscretions re: research consent and user privacy — the field poses tons of ethical challenges, if only in theory. How would you control who “spoke” to you? What’s to stop someone from sending you disturbing or abusive thoughts, or otherwise “hacking” your brain? And if these signals are moderated by some third-party technology, like a headset or helmet, will they be recorded somehow and saved, and by whom and for what purpose? Could they be hijacked by advertisers like the ones in “Minority Report,” who tailor interactive billboards to private thoughts?

“John Anderton!” one calls out, “you could use a Guinness right about now!”

There are, as of yet, no answers to these questions: An academic paper on the ethics of brain-to-brain technology, published in 2014, warned that there is neither legislation nor formal academic protocol for this type of research. (The writers predicted that could eventually provoke “public uproar.”)

For now, however, such concern is many breakthroughs and advances away. Zuckerberg himself may be getting up in years by the time we’re communicating telepathically.

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