On February 28, we published an article describing the first brain-to-brain interface:
Miguel Pais-Vieira, Mikhail Lebedev, Carolina Kunicki, Jing Wang & Miguel A. L. Nicolelis
Scientific Reports 3, doi:10.1038/srep01319
In brief, this interface interconnected two rats. One we called the “encoder”, the other – the “decoder”. While the encoder performed a two-choice task, its cortical signals were recorded with implanted electrodes, slightly processed (with a sigmoid transfer function) and transmitted to the brain of the decoder in the form of intracortical microstimulation. The decoder successfully learned to understand microstimulation and reproduced the encoder’s behavior with ~70% accuracy. It should be noted that, in addition to the communication channel from the encoder to the decoder, there was also a feedback loop from the decoder to the encoder: the encoder was rewarded each time the decoder got it right. This feedback encouraged the encoder to do a good job in generating a readable code.
Miguel Pais-Vieira — an extremely talented neuroscientist at Duke University — performed the major part of this tremendous experimental work. Jing Wang and Carolina Kunicki assisted him in the experiments. Curiously, Carolina handled rats many thousand miles away from Durham — in Natal, Brasil. The Durham and Natal rats were connected through Internet.
This work was greatly inspired by the ideas of Miguel Nicolelis who has been talking to us about brain-to-brain interfaces and various ways to implement them for quite a while, for more than two years already. Another Nicolelis’ dream has come true!
Although this first implementation of a brain-to-brain interface may seem to be relatively simple (see some critical comments below), the rat-to-rat dyad is relatively easily scalable to incorporate more than two rats. This is where the complexity will start — an “organic computer” according to Miguel Nicolelis. I think that many research laboratories will in the nearest future rush to implement “organic computers” made of several rats or other animals.
I was very happy to help Miguel Pais-Vieira with hopefully useful input on the experimental design, data analysis and writing. I think this is just the beginning for Miguel, Jr (Miguel, Sr — Miguel Nicolelis). Soon he will produce even more amazing results.
Interestingly, the paper received critical comments from our competitors in the field of brain-machine-interfaces. Here are these comments:
But Sliman Bensmaia, a neuroscientist from the University of Chicago in Illinois, says that if the goal is to make better neural prosthetics, “the design seems convoluted and irrelevant”. And if it is to build a computer, “the proposition is speculative and the evidence underwhelming”.
Bensmaia is developing an artificial sensation based on microstimulation of the primary somatosensory cortex, but to the best of my knowledge has not produced prominent publications on the topic. A semi-serious answer to this can be found in Wikipedia:
“In the process of developing an invention, the initial idea may change. The invention may become simpler, more practical, it may expand, or it may even morph into something totally different. Working on one invention can lead to others too.”
Lee Miller, a physiologist at Northwestern University in Evanston, Illinois, says that Nicolelis’s team has made many important contributions to neural interfaces, but the current paper could be mistaken for a “poor Hollywood science-fiction script”. He adds, “It is not clear to what end the effort is really being made.”
Miller is known for his work where cortical neurons were connected to a functional electrical stimulator that stimulated forearm muscles to reproduce hand grasping. Another semi-serious reply based on a Wikipedia quote:
“Play may lead to invention. Childhood curiosity, experimentation, and imagination can develop one’s play instinct—an inner need according to Carl Jung. Inventors feel the need to play with things that interest them, and to explore, and this internal drive brings about novel creations.”
But Andrew Schwartz, a neurobiologist at the University of Pittsburgh in Pennsylvania, notes that the decoders performed poorly, even though they had to solve only a basic task with just two choices. “Although this may sound like ‘mental telemetry’, it was a very simple demonstration of binary detection and binary decision-making,” he says. “To be of real interest, some sort of continuous spectrum of values should be decoded, transmitted and received.”
Schwartz is well known for his work on brain-machine interfaces. “Some sort of continuous spectrum”? Let’s not rush. Also from Wikipedia:
“Morse code is a method of transmitting text information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment.”
“It’s a pretty cool idea that they’re in tune with each other and working together,” said neuroscientist Bijan Pesaran of New York University. But Pesaran says he could use some more convincing that this is what’s actually going on. For example, he’d like to see the researchers extend the experiment to see if the rats on the receiving end of the brain-to-brain communication link could improve their performance even more. “If you could see them learning to do it better and faster, then I’d really be impressed.”
Pesaran is an expert in association cortical areas. “Better and faster?” But what if the first rat deliberately lies? From Wikipedia:
“Chinese whispers (or telephone in the United States) is a game played around the world, in which one person whispers a message to another, which is passed through a line of people until the last player announces the message to the entire group. Errors typically accumulate in the retellings, so the statement announced by the last player differs significantly, and often amusingly, from the one uttered by the first. Some players also deliberately alter what is being said in order to guarantee a changed message by the end of it.”
On a more serious note, I am not sure that it is appropriate and productive to place in popular media critical comments on a peer-reviewed scientific publication. If someone wants to criticize a scientific study, why not do it in scientific literature (or a blog), where the authors could then rebut the criticism? Popular articles by their nature cannot convey all the details of scientific controversies and may easily mislead the readers.
In any way, I think that a new era has just begun: the era of brain-to-brain interfaces.