The human brain has inspired artificial intelligence, which can perform a wide array of tasks, from diagnosing diseases to creating smart content. However, the brain, which is the original model, continues to outperform artificial intelligence in many ways. Therefore, it is better to work straight on the surface, than making AI more brain-like.
What are biocomputers?
Scientists from multiple disciplines are working to create revolutionary biocomputers, which could be faster, more efficient and more powerful than silicon-based computing and artificial intelligence, and will require only a fraction of the energy. In biocomputers, three-dimensional cultures of brain cells, called brain organoids, serve as biological hardware.
The study describing the roadmap to create biocomputers powered by human brain cells was recently published in the journal Frontiers in Science.
What is organoid intelligence?
According to the new study, ‘organoid intelligence’ describes an emerging multidisciplinary field working to develop biological computing using three-dimensional cultures of human brain cells and brain-machine interface technologies, and requires scaling up current brain organoids into complex, durable three-dimensional structures enriched with cells and genes associated with learning.
Organoid intelligence also involves connecting these brain organoids to next-generation input and output devices and artificial intelligence or machine learning systems.
For organoid intelligence to be a successful field, new models, algorithms and interface technologies must be taught to communicate with brain organoids, understand how they learn and compute, and process and store the massive amounts of data brain organoids will generate.
In a statement released by Frontiers, Professor Thomas Hartung of Johns Hopkins University, and one of the authors on the paper, said a community of top scientists has gathered to develop ‘organoid intelligence’, which they believe will launch a new era of fast, powerful and efficient biocomputing.
Would brain organoids make good computers?
A type of lab-grown cell cultures, brain organoids share important aspects of brain function and structure such as neurons and other brain cells that are essential for cognitive functions like learning and memory. Brain organoids are not ‘mini-brains’.
While most cell structures are flat, organoids have a three-dimensional structure, which increases the culture’s cell density 1,000-fold. This means that the neurons can form many more connections.
Hartung said while silicon-based computers are better with numbers, brains are better at learning. Citing the example of AlphaGo, the artificial intelligence that beat the world’s number one Go player in 2017, Hartung said it was trained on data from 1,60,000 games.
He stated that a person would have to play five hours a day for more than 175 years to experience these many games.
Not only are brains superior learners, but also more energy efficient. The amount of energy spent training AlphaGo is more than what is needed to sustain an active adult for a decade, the study said.
Hartung said brains also have an amazing capacity to store information, estimated at 2,500 terabytes.
He explained that humans are reaching the physical limits of silicon computers because they cannot pack more transistors into a tiny chip. However, the brain is wired completely differently, and has about 100 billion neurons linked through over 1,015 connection points.
Hartung said this is an enormous power difference compared to the world’s current technology.
What organoid intelligence biocomputers would look like
Organoid intelligence research could improve researchers’ understanding of brain development, learning, and memory, and potentially help find treatments for neurological disorders such as dementia, the study said.
Researchers can produce brain organoids from adult tissues using the groundbreaking technique developed by Nobel Laureates John Gurdon and Shinya Yamanaka. In 1962, Gurdon replaced the nucleus of a fertilised egg cell from a frog with the nucleus of an epithelial cell taken from a tadpole’s intestine, and saw that the cell grew into a new frog. This proved that the mature cell still contained the genetic information needed to form all types of cells.
How can organoid intelligence benefit humanity?
Using this technology, scientists can develop personalised brain organoids from skin samples of patients suffering from neurological disorders such as Alzheimer’s disease, the study said.
Hartung said with organoid intelligence, one can study the cognitive aspects of neurological conditions. He explained that one can compare memory formation in organoids derived from healthy people and from Alzheimer’s patients, and try to repair relative deficits.
According to Hartung, organoid intelligence can also be used to test whether certain substances, such as pesticides, cause memory or learning problems.
Current brain organoids need to be scaled-up for organoid intelligence, Hartung said.
He explained that brain organoids are too small, each containing about 50,000 cells. For organoid intelligence, the number of cells in brain organoids will have to be increased to 10 million.
The authors aim to adapt tools from scientific disciplines such as bioengineering and machine learning to develop technologies to communicate with the organoids. This means that using these technologies, researchers can send information to organoids, and read out what they are thinking.
Hartung said the researchers developed a brain-computer interface device that is a kind of an electroencephalogram (EEG) cap for organoids. The researchers presented the device in an article published in August 2022.
Hartung explained that the device 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.
According to the authors, there is a possibility that organoid intelligence will integrate a wide range of stimulation and recording tools in the future. In this way, researchers will be able to study interactions across networks of interconnected organoids.
Ethical aspects of organoid intelligence
The authors noted in the paper that an ’embedded ethics’ approach is important to ensure that organoid intelligence develops in an ethically and socially responsive manner. As part of this approach, interdisciplinary and representative teams of ethicists, researchers and members of the public will identify, discuss and analyse ethical issues.
Some of the ethical questions that arise when creating human brain organoids are whether they could develop consciousness, even in a rudimentary form, if they could experience pain and suffering, and what will be the rights of the people whose cells will be used to make brain organoids.
When will the first organoid intelligence become a reality?
Organoid intelligence is still in its infancy, yet, a new study published by Dr Brett Kagan, one of the authors on the paper published in Frontiers, has provided proof of the concept of organoid intelligence. Kagan’s team showed that a normal, flat brain cell culture can learn to play the video game Pong.
Hartung explained that Kagan’s team is already testing this with brain organoids, and replicating this experiment with organoids already fulfils the basic definition of organoid intelligence.
Hartung concluded that now, researchers need to build the community, the tools and the technologies to realise the full potential of organoid intelligence.
The authors concluded that the development of “intelligence-in-a-dish” offers unparalleled opportunities to elucidate the biological basis of human cognition, learning and memory, and can provide more insights into various disorders associated with cognitive deficits. Therefore, organoid intelligence could help identify novel therapeutic approaches to address major global unmet needs.