Connecting brains together into networks, or ‘mind-melding’ as the Trekkers say, has a long and colourful history in science fiction. But it’s also something that scientists are doing, rather successfully, with animals in the lab. And in many cases, networked animal brains seem to perform better than individual brains.
A pair of studies published today in the journal Scientific Reports detail some of the most sophisticated mind-networking efforts to date. By connecting brains with electrodes, researchers have shown that both rats and monkeys can coordinate their thoughts to carry out simple tasks, including pattern recognition and moving a robotic limb.
For years, neuroscientists have been building devices to decipher signals recorded by electrodes in the brain, so-called brain computer interfaces. At Duke University, North Carolina, neuroscientist Miguel Nicolelis and colleagues have been rigging up monkeys to brain-computer interfaces (BCI) and watching the animals control robotic arms. Perhaps unsurprisingly, they’ve learned that monkeys get better at wielding robot parts when more of their neurons are able to join in the effort.
That observation led the researchers to ponder a simple question: if more neurons from a single brain can do a job better, shouldn’t more brains be better than one?
The only logical thing to do was to link together a bunch of brains and see what happens. Over at The New York Times, Carl Zimmer describes the first round of experiments performed in rats:
Dr. Nicolelis and his colleagues began by implanting two sets of electrodes in the brains of four rats. One set delivered a signal into one part of each brain, while the other eavesdropped on a different brain patch.
The four rats received the same signal, and then a computer monitored how their brains responded. If all four rats produced synchronized signals in their brains, they were rewarded with a sip of water.
Through trial and error, the rats learned how to consistently synchronize their brains, making it possible for the rats to act like a simple computer. In one experiment, the animals learned how to produce different brain responses to two different signals: a single burst of electric pulses, or four bursts.
The rats learned how to produce synchronized brain activity in response to one of the signals, and unsynchronized activity in the other. Their collective response was correct as often as 87 percent of the time — substantially better than an individual rat learning on its own.
Encouraged by the success of their mind-melded rats, the scientists turned their attention back to monkeys and robot arms. This time around, they implanted electrodes into two monkeys instead of one:
Each monkey looked at a computer screen on which there were images of an arm and a ball. The computer combined the brain signals from both monkeys to move the arm. The two monkeys learned to work together to reliably move the arm to the ball, which produced a reward.
In another trial, one monkey learned to control the horizontal movement of the arm while the other monkey controlled its vertical movement by means of electrical brain impulses. In an even more ambitious test, the scientists programmed a virtual arm in three-dimensional space, allowing three monkeys to share control of different aspects of its movement.
Once again, the monkeys learned to move the arm to the ball. Even when one of the monkeys did a bad job of controlling the arm, the other two compensated to keep it on track.
These simple experiments are a far cry from the sort of brain networking portrayed in everything from Star Trek to Sense8. But even simple demonstrations of how brains can share electrical impulses and work together are exciting, as they’re paving a path to much more ambitious applications.
Imagine groups of physicists putting their heads together to solve an incredibly hard maths problem. Or a search-and-rescue team linking their brains in order to better coordinate their efforts. It’s also not hard to envision this technology infiltrating gaming, with networked MMO parties rising much more quickly through the ranks (I’m sure that’s been the plot of an anime show, or ten.)
Of course, mind-melding will raise a slew of thorny ethical and legal questions, as well. As Zimmer points out, if a brain network were to commit a crime, lawyers are going to have their hands full determining who exactly was responsible. But for now, at least, I say we just admire the fact that scientists are able to link brains together at all and observe a result. It's incredible. [New York Times]
You can read the full, open-access scientific paper here.
Top image via Star Trek Wiki