Telepathy has long been supernatural if not fiction but today hope is being actualized as the dream of making this phenomenon technological is looming the horizons.
In recent years, physicists and neuroscientists have developed an armory of tools that can sense certain kinds of thoughts and transmit information about them into other brains. That has made brain-to-brain communication a reality.
These tools include electroencephalograms (EEGs) that record electrical activity in the brain and trans-cranial magnetic stimulation (TMS), which can transmit information into the brain.
In 2015, Andrea Stocco and his colleagues at the University of Washington in Seattle used this gear to connect two people via a brain-to-brain interface. The people then played a 20 questions–type game.
An obvious next step is to allow several people to join such a conversation, and today Stocco and his colleagues announced they have achieved this using a world-first brain-to-brain network. The network, which they call BrainNet, allows a small group to play a collaborative Tetris-like game. “Our results raise the possibility of future brain-to-brain interfaces that enable cooperative problem-solving by humans using a ‘social network’ of connected brains,” they say.
The technology behind the network is relatively straightforward. EEGs measure the electrical activity of the brain. They consist of a number of electrodes placed on the skull that can pick up electrical activity in the brain.
A key idea is that people can change the signals their brain produces relatively easily. For example, brain signals can easily become entrained with external ones. So watching a light flashing at 15 hertz causes the brain to emit a strong electrical signal at the same frequency. Switching attention to a light flashing at 17 Hz changes the frequency of the brain signal in a way an EEG can spot relatively easily.
Together, these devices make it possible to send and receive signals directly to and from the brain. But nobody has created a network that allows group communication. Until now.
Stocco and his colleagues have created a network that allows three individuals to send and receive information directly to their brains. They say the network is easily scalable and limited only by the availability of EEG and TMS devices.
To do this, they vary the signal their brains produce. If the EEG picks up a 15 Hz signal from their brains, it moves a cursor toward the right-hand side of the screen. When the cursor reaches the right-hand side, the device sends a signal to the receiver to rotate the block.
The senders can control their brain signals by staring at LEDs on either side of the screen—one flashing at 15 Hz and the other at 17 Hz.
The receiver, attached to an EEG and a TMS, has a different task. The receiver can see only the top half of the Tetris screen, and so can see the block but not how it should be rotated. However, the receiver receives signals via the TMS from each sender, saying either “rotate” or “do not rotate.
But the question they investigate is whether humans can work out what to do when the data rates are so low. It turns out humans, being social animals, can distinguish between the correct and false information using the brain-to-brain protocol alone.