Researchers are collaborating across multiple fields to create biocomputers that use three-dimensional cultures of brain cells, called brain organoids, as biological hardware. They have outlined their plan to achieve this goal in the scientific journal Frontiers in Science.
Despite AI’s impressive track record, its computational power pales in comparison to a human brain. Now scientists are unveiling a revolutionary way to drive computing forward: Organoid intelligence, in which lab-grown brain organoids act as biological hardware.
Artificial intelligence (AI) has long been inspired by the human brain. This approach proved to be very successful: AI boasts impressive achievements – from diagnosing medical conditions to composing poetry. Yet the original model continues to outperform machines in many ways. This is why, for example, we can ‘prove our humanity’ with trivial image tests online. What if, instead of trying to make artificial intelligence more brain-like, we went straight to the source?
Researchers across multiple disciplines are working to create revolutionary biocomputers, where three-dimensional cultures of brain cells, called brain organoids, serve as biological hardware. They describe their roadmap to realize this vision in the journal Frontiers in Science.
A magnified image of a laboratory-grown brain organoid with fluorescent labeling for different cell types. (Pink – neurons; red – oligodendrocytes; green – astrocytes; blue – all cell nuclei). Credit: Thomas Hartung, Johns Hopkins University
“We call this new interdisciplinary field ‘organoid intelligence’ (OI),” said Prof Thomas Hartung of Johns Hopkins University. “A community of top researchers has come together to develop this technology, which we believe will launch a new era of fast, powerful and efficient biocomputing.”
What are brain organoids and why would they make good computers?
Brain organoids are a type of laboratory-grown cell culture. Although brain organoids are not ‘mini-brains’, they share key aspects of brain function and structure, such as neurons and other brain cells essential for cognitive functions such as learning and memory. While most cell cultures are flat, organoids also have a three-dimensional structure. This increases the culture’s cell density 1,000-fold, meaning neurons can form many more connections.
But even if brain organoids are a good mimic of brains, why would they make good computers? After all, aren’t computers smarter and faster than brains?
Organoid Intelligence: The New Frontier in Biocomputing Infographics. Credit: Frontiers/John Hopkins University
“While silicon-based computers are certainly better with numbers, brains are better at learning,” Hartung explained. “For example, AlphaGo (the AI that beat the world’s number one Go player in 2017) was trained on data from 160,000 games. A person would have to play five hours a day for more than 175 years to experience this many games.”
Brains are not only superior learners, they are also more energy efficient. For example, the amount of energy used to train AlphaGo is more than is needed to sustain an active adult for a decade.
“Brains also have an amazing capacity to store information, estimated at 2,500 TB,” Hartung added. “We’re reaching the physical limits of silicon computers because we can’t pack more transistors into a small chip. But the brain is wired completely differently. It has about 100 billion neurons connected through over 1015 connection points. That’s a huge difference in power in compared to our current technology.”
Organoid Intelligence: The New Frontier in Biocomputing Infographics. Credit: Frontiers/John Hopkins University
What would biocomputers with organoid intelligence look like?
According to Hartung, current brain organoids must be scaled up to OI. “They are too small and each contains about 50,000 cells. For OI, we would have to increase this number to 10 million,” he explained.
In parallel, the authors are also developing technologies to communicate with the organoids: in other words, to send them information and read out what they ‘think’. The authors plan to adapt tools from different scientific disciplines, such as bioengineering and machine learningas well as develop new stimulation and recording devices.
Organoid intelligence requires different technologies to communicate with the brain organoid infographic. Credit: Frontiers/John Hopkins University
“We developed a brain-computer interface device that is a kind of EEG cap for organoids, which we presented in a paper published last August. It is a flexible shell densely covered with tiny electrodes that can pick up both signals from the organoid and send signals to it,” Hartung said.
The authors envision that OI would eventually integrate a wide range of stimulation and recording tools. These will orchestrate interactions across networks of interconnected organoids that implement more complex computations.
Organoid intelligence may help prevent and treat neurological conditions
OI’s promise goes beyond computers and medicine. Thanks to a pioneering technique developed by Noble Laureates John Gurdon and Shinya Yamanaka, brain organoids can be produced from adult tissue. This means that researchers can develop personalized brain organoids from skin samples from patients suffering from neural disorders such as Alzheimer’s disease. They may then run more tests to examine how genetic factors, medications and toxins affect these conditions.
Organoid intelligence will advance medical research and innovation infographic. Credit: Frontiers/John Hopkins University
“With OI, we could also study the cognitive aspects of neurological conditions,” Hartung said. “For example, we could compare memory formation in organoids derived from healthy people and from Alzheimer’s patients, and try to repair relative deficits. We could also use OI to test whether certain substances, such as pesticides, cause memory or learning problems.”
Takes ethical considerations into account
Creating human brain organoids that can learn, remember and interact with their environment raises complex ethical questions. For example, could they develop consciousness, even in a rudimentary form? Can they experience pain or suffering? And what rights would people have regarding brain organoids made from their cells?
‘Embedded ethics’ will ensure responsible development of organoid intelligence infographics. Credit: Frontiers/John Hopkins University
The authors are very aware of these problems. “An important part of our vision is to develop OI in an ethical and socially responsible way,” said Hartung. “For this reason, we have collaborated with ethicists from the outset to establish an ’embedded ethics’ approach. All ethical issues will be continually assessed by teams of scientists, ethicists and the public as the research develops.”
How far are we from the first organoid intelligence?
Although OI is still in its infancy, a recently published study by one of the paper’s co-authors—Dr. Brett Kagan from Cortical Labs – proof of concept. His team showed that a normal, flat brain cell culture can learn to play the video game Pong.
“Their team is already testing this with brain organoids,” Hartung added. “And I would say that replicating this experiment with organoids already fulfills the basic definition of OI. From here, it’s just a matter of building the community, the tools and the technologies to realize the full potential of OI,” he concluded.
Reference: “Organoid intelligence (OI): the new frontier in biocomputing and intelligence-in-a-dish” by Lena Smirnova, Brian S. Caffo, David H. Gracias, Qi Huang, Itzy E. Morales Pantoja, Bohao Tang, Donald J. Zack, Cynthia A. Berlinicke, J. Lomax Boyd, Timothy D. Harris, Erik C. Johnson, Brett J. Kagan, Jeffrey Kahn, Alysson R. Muotri, Barton L. Paulhamus, Jens C. Schwamborn, Jesse Plotkin, Alexander S. Szalay, Joshua T. Vogelstein, Paul F. Worley, and Thomas Hartung, February 27, 2023, Frontiers in Science.
DOI: 10.3389/fsci.2023.1017235