Scientists have taught brain cells how to play the video game Pong, and they now plan to experiment with getting them drunk.
As the cells, taken from humans and mice, played the game, they learned. They played longer rallies and were aced less often.
That the 800,000 cells have mastered a version of the cult 1970s video game is evidence they can exhibit sentience, the Melbourne-based researchers said.
Their peer-reviewed study has been published in the journal Neuron.
Pong was an arcade game released in 1972 where two players use paddles to bat a ball back and forth – making a “pong” noise upon contact, hence the name.
Pong was hugely successful, and extremely simple. Its simplicity and iconic status prompted the researchers to choose it for their initial test.
The team, from Cortical Labs and universities including Monash University, the University of Melbourne and University College London, used human cells derived from stem cells and mouse cells derived from embryonic cells.
They put them on to the “DishBrain”, a multi-electrode array that can sense cell activity and stimulate the cells, then gave the cells feedback on whether the paddle was hitting the ball.
It worked, and within five minutes the cells started to “learn” how to play the simulated game using a shared “language” of electrical activity.
Over time they were less likely to be aced, and were able to have longer rallies – and the human cells could rally for longer than the mice (humans and mice were not pitched against each other).
The cell groups played 486 “games”, with researchers testing their reaction to different stimuli or lack thereof. For example, in some games they were given feedback either through giving the cells information or by removing information. In other games there was no feedback, so cells could not learn how their behaviour affected the environment.
Those with feedback learned from it.
Now the researchers will see how the cells perform when they are drunk or given medicines. They hope to use the DishBrain to learn more about conditions such as epilepsy and dementia.
The study’s lead author, Dr Brett Kagan, is the chief scientific officer of biotech startup Cortical Labs. He said by manipulating the neurons and showing that they change behaviour based on feedback, the team has shown “something that resembles intelligence”.
“This is the new way to think about what a neuron is,” he said.
“It’s not necessarily a computer, but it’s a small biological device that can process information and respond intelligently with incredible speed, low power consumption and flexibility.”
DishBrain is a model of the brain that would allow them to experiment with different inputs.
“We’re trying to create a dose response curve with ethanol – basically get them ‘drunk’ and see if they play the game more poorly, just as when people drink,” Kagan said.
Dr Adeel Razi, the director of Monash University’s computational and systems neuroscience laboratory, said the ability to teach cell cultures to “perform a task in which they exhibit sentience … opens up new discovery possibilities which will have far-reaching consequences for technology, health and society”.
“We know our brains have the evolutionary advantage of being tuned over hundreds of millions of years for survival,” he said.
“Now, it seems we have in our grasp [the ability to] harness this incredibly powerful and cheap biological intelligence.”
Another co-author, Prof Karl Friston from UCL, said the pioneering work allowed neurons to experience sensations.
“Remarkably, the cultures learned how to make their world more predictable by acting upon it,” he said.
“This is remarkable because you cannot teach this kind of self-organisation; simply because – unlike a pet – these mini brains have no sense of reward and punishment.”
That has allowed them to design a “sandbox” made of the same elements in an actual brain where they can test interventions.
The authors wrote in the Neuron article that a synthetic biological intelligence, “previously confined to the realm of science fiction”, could now be within reach.
