Biocomputers will be the next frontier to handle the massive required computational power
Although computers driven by human brain cells may sound like science fiction, a team of US researchers believes such machines, which are part of a new field dubbed “organoid intelligence”, could impact the future. And they now have a strategy to get there.
According to CNN, organ-like tissues created in the laboratory are called organoids. These three-dimensional models, which are typically created from stem cells, have been employed in laboratories for almost 20 years. This has allowed researchers to conduct studies on kidney, lung, and other organ-like models without hurting humans or animals.
The pen-dot-sized cell cultures that make up brain organoids don’t actually resemble miniature replicas of the human brain, but they do include neurons that can do brain-like tasks and connect in a myriad of ways.
In 2012, Dr. Thomas Hartung started developing brain organoids by modifying samples of human skin at the Johns Hopkins Bloomberg School of Public Health and Whiting School of Engineering in Baltimore.
He and his colleagues hope to employ the potential of brain organoids to create biological technology that consumes less energy than supercomputers. These “biocomputers” would make use of networks of brain organoids to possibly transform drug testing for conditions like Alzheimer’s, give information about the human brain, and alter computing in the future.
The research revealing Hartung and his team’s plan for organoid intelligence was released in the journal Frontiers in Science.
“Computing and artificial intelligence have been driving the technology revolution but they are reaching a ceiling”, said Hartung, senior study author, in a statement. “Biocomputing is an enormous effort of compacting computational power and increasing its efficiency to push past our current technological limits”.
Whereas human mental processes serve as a model for artificial intelligence, the technology cannot completely imitate the human brain. A supercomputer can process enormous volumes of data far more quickly than a human.
“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 these many games”.
The human brain, on the other hand, uses energy more effectively and is better at learning and coming to complicated logical conclusions. It is easily capable of tasks that a machine cannot perform, such as being able to distinguish one animal from another.
A $600 million supercomputer called Frontier weighs a heavy 8,000 pounds (3,629 kg), with each cabinet weighing the same as two regular pickup trucks. It is located at the Oak Ridge National Laboratory in Tennessee. The machine’s processing power surpassed that of a single human brain in June, but Hartung said it required a million times more energy.
“The brain is still unmatched by modern computers”, Hartung said.
“Brains also have an amazing capacity to store information, estimated at 2,500 (terabytes)”, he added. “We’re reaching the physical limits of silicon computers because we cannot pack more transistors into a tiny chip”.
John B. Gurdon and Shinya Yamanaka, pioneers in the field of stem cells, were awarded the Nobel Prize in 2012 for their work on a method that made it possible to create cells from fully grown tissues, such as skin. With the help of ground-breaking research, researchers like Hartung were able to create brain organoids that mimicked living brains and test and detect medications that may be harmful to the health of the brain.
Some scientists once questioned Hartung about whether brain organoids were capable of thought and consciousness. He thought about feeding organoids knowledge about their environment and how to interact with it in response to the question.
“This opens up research on how the human brain works”, said Hartung, who is also the co-director of the Center for Alternatives to Animal Testing in Europe. “Because you can start manipulating the system, doing things you cannot ethically do with human brains”.
Hartung describes organoid intelligence as “reproducing cognitive functions, such as learning and sensory processing, in a lab-grown human-brain model”.
For OI or organoid intelligence, Hartung would need to scale up the brain organoids he currently uses. Each organoid contains roughly the same amount of cells as the nervous system of a fruit fly. A single organoid is equivalent to around 800 megabytes of memory storage because it is one-three millionth the size of the human brain.
In order to share information with the organoids and get readouts of what they are “thinking”, the researchers also need a means of communication with them. The study’s authors have created a blueprint that combines new developments with technologies from bioengineering and machine learning. According to the study’s authors, more complex activities would be possible if organoid networks were to support various types of input and output.
“We developed a brain-computer interface device that is a kind of an EEG (electroencephalogram) cap for organoids, which we presented in an article 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”.
According to the researchers, human medicine may be where organoid intelligence makes its most significant contributions. Scientists could create brain organoids from skin samples of people with neural disorders, allowing them to study the effects of various drugs and other factors.
“With OI, we could study the cognitive aspects of neurological conditions as well”, 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”.
Moreover, brain organoids may provide a new perspective on how people think.
“We want to compare brain organoids from typically developed donors versus brain organoids from donors with autism”, said study co-author and co-investigator Lena Smirnova, a Johns Hopkins assistant professor of environmental health and engineering, 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 for autism, without having to use animals or to access patients, so we can understand the underlying mechanisms of why patients have these cognition issues and impairments”, she said.
But, there are already encouraging outcomes that show what is feasible. Video game Pong can be learned by brain cells, according to research co-author Dr. Brett Kagan, chief scientific officer at Cortical Laboratories in Melbourne, Australia, and his team.
The use of brain organoids to generate organoid intelligence is currently in its very early stages. According to Hartung, it could take decades to develop an OI that has mouse-like cognitive abilities comparable to those of computers.
“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 hereon, it’s just a matter of building the community, the tools, and the technologies to realize OI’s full potential”.
The creation of human brain organoids that can perform cognitive tasks poses several ethical questions, such as whether the organoids may experience consciousness or pain and if the people whose cells were used to create them have any legal claim to the organoids.
“A key part of our vision is to develop OI in an ethical and socially responsible manner”, Hartung said. “For this reason, we have partnered with ethicists from the very beginning to establish an ‘embedded ethics’ approach. All ethical issues will be continuously assessed by teams made up of scientists, ethicists, and the public, as the research evolves”.
In a separately released policy viewpoint, Julian Kinderlerer, professor emeritus of intellectual property law at the University of Cape Town in South Africa, stressed the importance of including the general public in the understanding and advancement of organoid intelligence, although Kinderlerer was not part of the current 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 assuring that any experimentation is within ethical boundaries yet to be determined”.
We got used to computers consisting of hardware and software. Now we are going to have to get used to dealing with computers that also have a biological component. This merging of biology and electronics opens up even more complex considerations than the risks of technology alone such as AI. The ethical implications are not that easy to deal with. Can such neurons be considered truly alive? Will they be able to become sentient, but trapped inside a computer? The questions are many, and the answers are not simple. Nevertheless, it is wise to do all the necessary considerations before creating something from which there will be no turning back.