A petri dish of human brain cells currently powers the game Doom. Should we be worried? | games

IIt sounds like the opening of a science fiction movie, but US scientists recently uploaded a copy of the brain of a live fly into a simulator. In San Francisco, biotechnology company Eon Systems has created a virtual insect that knows how to walk, fly, groom and feed in its virtual environment. Meanwhile, researchers in Australia taught a petri dish containing 200,000 human brain cells to play the popular 1990s shooter Doom. One experiment pushed the brain into a computer; The other connected a computer to brain cells.

Both stories were hailed as scientific breakthroughs, but they also raised inevitable concerns about the possibilities of producing humans in a laboratory and digital cloning. Should we be worried?

It was Australian startup Cortical Labs in Melbourne that taught a dish of lab-grown neurons to play ping-pong in 2022. Now it has built what it describes as “the world’s first deployable biological computer,” running on living human tissue rather than silicon chips, and which happily plays the 1993 shooter Doom.

“In the world of computer nerds, there is an obsession with running Doom on everything from calculators to microwaves,” Cortical Labs CEO Li Hon Wing Chung said via Zoom from Melbourne. “Once we got Pong working, the first thing people said was, ‘When are you going to do Doom?’

The average human brain contains about 86 billion neurons, which is equivalent to about 430,000 petri dishes. But how do you harvest 200,000 brain cells without resorting to a saw and an ice cream scoop?

“It’s actually my brain cells, at least most of them are,” Chung says proudly. “There is no scraping or extraction of the brain. It is a very remarkable technique developed by Professor Shinya Yamanaka, who won the Nobel Prize in 2012.”

All you need is 10 ml of blood (in this case Zhong’s blood), from which about 100 white blood cells can be harvested. They can then be reprogrammed into induced pluripotent stem cells (iPSCs) – the body’s biological building blocks – which can then be reproduced dramatically.

“Basically, we reverse the biological clock back to the embryonic state, stimulate it on neurons, and put it on a glass slide about the size of a 50p piece,” Chung explains. “Because it’s on a chip — and electricity is the common language between neurons and the computer system — we can interact with it and make it play Doom.”

Cortical Labs ran Pong’s trial in-house, but this time reached out to 24-year-old Singaporean Sean Cole, who had just completed a master’s degree in artificial intelligence at the University of Sussex, and whose father happened to be a colleague of its CEO. Cole wrote the code remotely, and the team then tested it on their local machines.

“I was a little surprised that it worked the first time,” he told me over Zoom.

So how can a petri dish of brain cells play Doom when it doesn’t have any eyes? Or fingers? “We take a snapshot of the game that includes information like the player’s health and the location of enemies, then we pass it through a neural network, convert it to numbers, and then send the data,” Cole explains. “This is called encoding – essentially converting the game state into signals that the neurons can understand. The neurons then fire off an output – move left, move right, move forward, shoot or don’t shoot – which the system decodes and turns back into actions in the game.”

“If you think about how humans work, we have information going into our retina, which is converted into electrical signals, which are processed in the brain, and then output occurs,” Chung adds. “It’s really no different.”

If a computer full of brain cells is playing a video game and making decisions, does that mean it’s conscious? Or does he act like a regular Doom player? “People have different perceptions of what consciousness is,” Cole says. “I certainly don’t think he’s conscious. At first he didn’t know how to move or aim or even shoot. Then he shoots the first two enemies and stops — almost as if he’s keeping himself safe. So he’s definitely learning. We’ve been able to control the brain to learn in a very controlled environment. The next step could be something like Neuralink, where you inject a chip into the brain to train someone to learn language faster.”

How cells learn how to play the game is unclear. “We can hypothesize that it might include things like the free energy principle — the idea that living systems work to minimize free energy — or Hebbian learning, where connections between neurons strengthen when they fire together.” Can we use such technology to learn kung fu instantly, like in the movie The Matrix? “If we find a way to securely connect this technology to humans, these could be the implications,” Cole says. “The big worry would be: What if I override someone’s memories?”

While Chung says he’d like to try making neurons play Pokémon next, the real future application here isn’t in getting slices of human neurons to graduate to playing Minecraft or Grand Theft Auto, but in medicine. “People look at it from the angles of biomedical research, for disease modeling,” he says. “Things like epilepsy, where drugs can be tested on neurons grown outside the body — not just to discover new drugs, but to personalize them.”

Meanwhile, in San Francisco, where Eon Systems scanned the brain of a fruit fly and recreated it as a virtual insect, the big scientific news is that the team has essentially recreated the creature’s behavioral wiring. The digital insect already knew how to behave like a fly, without any training or prompting. This challenges the central assumption of modern artificial intelligence: that intelligence must be acquired. In the case of the fly, much of its behavior seems to be built into itself.

“The brain was examined using an electron microscope,” says Michael Andrej, CEO of Eon Systems. “Our head of engineering led a project to simulate that brain, and now we have put the simulated brain back into the body, so it can walk around in a virtual world.”

The fruit fly brain consists of about 140,000 neurons, the equivalent of about five petri dishes. The virtual fly has 87 joints and can do almost anything an actual fly can do. But does he realize that he is living in a simulation?

“The fly probably knows something is wrong, because we’re not simulating the environment very accurately,” Andrej says. “We can’t give very specific taste and smell signals – just that something smells sweet or tastes bitter, but there are no complex odors.”

Andrej suggests that brain simulation could eventually allow humans “to thrive in a superintelligent world. Our goal is to make the simulation and the computed brain and body feel indistinguishable from the normal biochemical body and brain.” “If it’s different, we’ve done something wrong.”

But we’re still a long way from the “self-uploading to the Internet” future envisioned in Devs or The Lawnmower Man, mainly because, in this case, the fly’s brain has to be removed from the body first. “Scanning the body was very difficult,” says Andrej, which will likely reduce the waiting list of human volunteers wanting to try the technology.

Meanwhile, Zhong believes that biological computing can achieve things that traditional computing has struggled with. “There’s something called the Moravec paradox, which is well-known in robotics: what humans find very difficult, computers find easy, and what computers find difficult, humans find easy,” he says.

“Abstract thinking, mathematics and language are relatively recent things in evolutionary terms, which is partly why computers excel at them. But motor control and probabilistic decision making are things we inherited over millions of years of evolution. Robots may be very good at solving mathematical problems, but we are still trying to build robots that can walk properly.” He says biological systems, such as fruit fly mimics, may eventually power robots, drones and other machines that need to navigate the unpredictable real world.

Right now, humanity’s first biological computer is busy doing what humans have always done with new technology: playing games. And somewhere in Silicon Valley, a fruit fly is living its second life inside a computer, completely unaware that it is living in an insect matrix.