In a study that for the first time establishes the feasibility of direct brain-to-brain communication, an international group of researchers has successfully shown it is possible to non-invasively transmit a thought from one person to another 5,000 miles away, without either of them having to speak or write.

Indeed, in a paper on the work published in PLOS ONE, the authors argue that what the study shows should probably be termed “mind-to-mind” transmission as opposed to “brain-to-brain,” because “both the origin and the destination of the communication involved the conscious activity of the subjects.”

In the brain-to-brain equivalent of “instant messaging,” the study shows how the international team of neuroscientists and robotics engineers used various “neurotechnologies” to send messages via the Internet between the intact scalps of two human subjects over 5,000 miles apart – one in India and the other in France.

The team included members from Beth Israel Deaconess Medical Center (BIDMC), a teaching affiliate of Harvard Medical School (HMC) in Boston, MA, Starlab Barcelona in Spain, and Axilum Robotics in Strasbourg, France.

Co-author Alvaro Pascual-Leone, Director of the Berenson-Allen Center for Noninvasive Brain Stimulation at BIDMC and HMC Professor of Neurology, explains how they wanted to discover if it was possible to send messages between two people by reading out the brain activity from one into the other, and to do it across a great distance, using existing communication pathways:

One such pathway is, of course, the Internet, so our question became – could we develop an experiment that would bypass the talking or typing part of Internet and establish direct brain-to-brain communication between subjects located far away from each other in India and France?”

And they proved that the answer to their question was “Yes.”

The team chose to transmit thoughts from India to France using two brain technologies linked by a computer brain interface via the Internet: electroencephalogram (EEG) and robot-assisted and image-guided transcranial magnetic stimulation (TMS).

illustration of people with connected brainsShare on Pinterest
The team believes the findings are an important step toward exploring whether it is possible to communicate from mind to mind without the use of language or gestures.

Previous studies have already shown that a person can have a conscious thought about moving an arm or a leg, and that thought can be conveyed via EEG-based brain-computer interaction to a computer that passes it to a robot that moves a limb or controls a wheelchair.

But this new study takes that a stage further by adding a second human brain to the other end of the communication system.

The researchers recruited four healthy volunteers – aged between 28 and 50 – to take part in a number of experiments. One was the sender – based in India, and the other three were receivers of the messages and had to understand them – they were based in France.

The EEG picked up the “thoughts” in the sender – the greeting “hola” (which means “hello” in Catalan or Spanish) or “ciao” (“hello” or “goodbye” in Italian) – which were then assigned to the brain-computer interface to send as a binary code by email from India to France. In France, a computer-brain interface translated the thoughts into signals that passed through the scalps of the receivers as non-invasive brain stimulations with the help of robotized TMS.

The receivers experienced the brain stimulations as “phosphenes” – flashes of light on the periphery of their vision. The flashes appeared in numerical sequences that the receivers could then decode into the messages.

The team carried out similar experiments between Spain and France. The final results showed an error rate of only 15%, with 5% error rate on the sending side and 11% error rate on the receiving side.

Prof. Pascual-Leone says thanks to the advanced precision neuro-technologies, namely the wireless EEG at the sending end and the robotized TMS at the receiving end, they directly and non-invasively transmitted thoughts from one person to another, without them having to speak or write, and adds:

This in itself is a remarkable step in human communication, but being able to do so across a distance of thousands of miles is a critically important proof-of-principle for the development of brain-to-brain communications.”

The team believes the findings are an important step toward exploring whether it is possible to communicate from mind to mind without the use of language or gestures.

Transcranial magnetic stimulation (TMS) is a relatively new method of pain-free stimulation of brain cells. In 2011, researchers described in two studies how they discovered the activity of distinct brain cell types changed with different TMS patterns.