“Organoid intelligence” could create brain cell-led computers

(CNN) Computers powered by human brain cells may sound like science fiction, but a team of researchers in the US believe such machines, part of a new field called “organoid intelligence”, could shape the future – and now they have a plan to get there.

Organoids are laboratory-grown tissues that resemble organs. These three-dimensional structures, usually derived from stem cells, have been used in laboratories for nearly two decades, where researchers have been able to avoid harmful human or animal experiments by experimenting on stand-ins for kidneys, lungs and other organs.

Brain organoids don’t actually resemble tiny versions of the human brain, but the pen-dot-sized cell cultures contain neurons capable of brain-like functions, forming a multitude of connections.

Researchers call the phenomenon “intelligence in a dish”.

Dr. Thomas Hartung, a professor of environmental health and engineering at the Johns Hopkins Bloomberg School of Public Health and the Whiting School of Engineering in Baltimore, began growing brain organoids by modifying human skin samples in 2012.

He and his colleagues envision combining the power of brain organoids into a type of biological hardware that is more energy efficient than supercomputers. These “biocomputers” will use networks of brain organoids to potentially revolutionize pharmaceutical testing for diseases such as Alzheimer’s, provide insight into the human brain and change the future of computing.

Research detailing the plan for organoid intelligence laid out by Hartung and his colleagues was published Tuesday in the journal Frontiers in Science.

“Computing and artificial intelligence have driven the technology revolution, but they are reaching a ceiling,” Hartung, senior study author, said in a statement. “Biocomputing is a huge effort to compress computational power and increase efficiency to push past our current technological limits.”

The human brain vs. artificial intelligence

While artificial intelligence is inspired by human thought processes, the technology cannot fully replicate all the functions of the human brain. This gap is why humans can use an image- or text-based CAPTCHA, or a fully automated public Turing test to tell computers and humans apart, as an online security measure to prove they’re not robots.

The Turing test, also known as the imitation game, was developed in 1950 by the British mathematician and computer scientist Alan Turing to assess how machines display intelligent human-like behavior.

But how does a computer really compare to a human brain?

A supercomputer can crunch huge amounts of numbers faster than a human can.

“For example, AlphaGo (the AI ​​that beat the world’s No. 1 Go player in 2017) was trained on data from 160,000 games,” Hartung said. “A person would have to play five hours a day for more than 175 years to experience this many games.”

On the other hand, a human brain is more energy efficient in addition to learning and making complex logical decisions. Something as basic as being able to distinguish one animal from another is a task the human brain can easily do that a computer cannot.

Frontier, a $600 million supercomputer at Oak Ridge National Laboratory in Tennessee, weighs a hefty 8,000 pounds (3,629 kilograms), with each cabinet weighing the equivalent of two standard pickup trucks. The machine exceeded the computational capacity of a single human brain in June — but it used a million times more energy, Hartung said.

“The brain is still unmatched by modern computers,” Hartung said.

“Brains also have an incredible capacity to store information, estimated at 2,500 (terabytes),” he added. “We’re reaching the physical limits of silicon computers because we can’t pack more transistors into a small chip.”

How a biocomputer might work

Stem cell pioneers John B. Gurdon and Shinya Yamanaka received a Nobel Prize in 2012 for developing a technique that made it possible to generate cells from fully developed tissues such as skin. The groundbreaking research allowed researchers like Hartung to develop brain organoids that were used to mimic living brains and test and identify drugs that may pose a risk to brain health.

Hartung recalled being asked by other researchers whether brain organoids could think or achieve consciousness. The question spurred him to consider providing information to organoids about their environment and how to interact with it.

“This opens up research into how the human brain works,” said Hartung, who is also co-director of the Center for Alternatives to Animal Testing in Europe. “Because you can start manipulating the system, doing things you can’t ethically do with human brains.”

Hartung defines organoid intelligence as “reproducing cognitive functions, such as learning and sensory processing, in a laboratory-grown human brain model.”

The brain organoids that Hartung currently uses must be scaled up for OI, or organoid intelligence. Each organoid has about the number of cells you would find in a fruit fly’s nervous system. A single organoid is about one-three-millionth the size of the human brain, which means it is equivalent to about 800 megabytes of memory storage.

“They are too small, and each contains about 50,000 cells. For OI, we need to increase this number to 10 million,” he said.

The researchers also need ways to communicate with the organoids to send them information and receive readings of what the organoids are “thinking”. The study authors have developed a blueprint that includes tools from biotechnology and machine learning, along with new innovations. Allowing different types of input and output across organoid networks will allow for more complex tasks, the researchers wrote in the study.

“We developed a brain-computer interface device that is a kind of EEG (electroencephalogram) cap for organoids, which we presented in a paper published last August,” Hartung said. “It is a flexible shell that is densely covered with tiny electrodes that can both pick up signals from the organoid and transmit signals to it.”

Hartung hopes one day there will be a beneficial communication channel between AI and OI “that will allow the two to explore each other’s capabilities.”

Ways to use OI

The most impactful contributions to organoid intelligence may manifest in human medicine, the researchers said.

Brain organoids can be developed from skin samples of patients with neural disorders, allowing researchers to test how different drugs and other factors might affect them.

“With OI, we could also study the cognitive aspects of neurological conditions,” Hartung said. “For example, we can compare memory formation in organoids derived from healthy people and from Alzheimer’s patients, and try to repair relative deficits. We can also use OI to test whether certain substances, such as pesticides, cause memory or learning problems.”

Brain organoids may also open up a new way of understanding human cognition.

“We want to compare brain organoids from typically developed donors versus brain organoids from donors with autism,” study co-author and co-investigator Lena Smirnova, a Johns Hopkins assistant professor of environmental health and engineering, said in a statement.

“The tools we are developing towards biological computing are the same tools that will allow us to understand changes in neuronal networks specific to autism, without having to use animals or have access to patients, so we can understand the underlying mechanisms of why patients have this cognition problems and impairments,” she said.

Using brain organoids to create organoid intelligence is still very much in its infancy. Developing OI comparable to a computer with the brain power of a mouse could take decades, Hartung said.

But there are already promising results that illustrate what is possible. Study co-author Dr. Brett Kagan, chief scientific officer at Cortical Labs in Melbourne, Australia, and his team recently showed that brain cells can learn to play Pong, the video game.

“Their team is already testing this with brain organoids,” Hartung said. “And I would say that replicating this experiment with organoids already fulfills the basic definition of OI. From now on, it’s just a matter of building the community, tools and technologies to realize OI’s full potential.”

The ethics of brain organoids

Creating human brain organoids capable of cognitive functions raises a number of ethical concerns, including whether they can develop consciousness or feel pain, and whether those whose cells were used to create them have any rights regarding the organoids.

“A central part of our vision is to develop OI in an ethical and socially responsible way,” said Hartung. “For this reason, we have worked with ethicists from the outset to establish an ’embedded ethics’ approach. All ethical issues will be continually reviewed by teams of researchers, ethicists and the public, as the research evolves.”

Involving the public in the understanding and development of organoid intelligence is essential, wrote Julian Kinderlerer, professor emeritus of intellectual property rights at the University of Cape Town in South Africa, in a separately published policy perspective. Kinderlerer was not involved in the new OI study.

“We are entering a new world, where the interface between humans and human constructs blurs distinctions,” Kinderlerer wrote. “Society cannot passively await new discoveries; it must be involved in identifying and resolving possible ethical dilemmas and ensuring that any experimentation is within ethical boundaries that have yet to be determined.”

Seeing the development of artificial intelligence such as ChatGPT has led some to question how close computers are to passing the Turing test, writes Gary Miller, vice dean for research strategy and innovation and professor of environmental health sciences at Columbia University in New York City, in a separate Viewpoint article published Tuesday. Miller was not involved in the Johns Hopkins study.

While ChatGPT can effectively collect information on the internet, it cannot respond to a temperature change the way a cultured cell system can, he wrote.

“Brain organoid systems may display key aspects of intelligence and sensing,” Miller wrote.

“This requires a robust examination of the ethical implications of the technology, in which ethicists must be included. We must ensure that each step of the process is carried out with scientific integrity, while recognizing that the larger issue is the potential impact on society. OI blurs the line between human cognition and machine intelligence, and technology and biology are advancing at a rate that may outpace the ethical and moral discussions necessary.This emerging field must take a vigorous approach to addressing the ethical and moral questions that accompany these kinds of scientific advances and must do so before the technology crashes into the moral abyss.”