A Florida scientist has developed a “brain” in a glass dish that is capable of flying a virtual fighter plane and could enhance medical understanding of neural disorders such as epilepsy.
The “living computer” was grown from 25,000 neurons extracted from a rat’s brain and arranged over a grid of 60 electrodes in a Petri dish.
The brain cells then started to reconnect themselves, forming microscopic interconnections, said Thomas DeMarse, professor of biomedical engineering at the University of Florida.
“It’s essentially a dish with 60 electrodes arranged in a dish at the bottom,” explained DeMarse, who designed the study.
“Over that we put the living cortical neurons from rats, which rapidly begin to reconnect themselves, forming a living neural network — a brain.”
Although such living networks could one day be used to fly unmanned aircraft, DeMarse said the study was of more immediate relevance as an experimental aid to understanding how the human brain performs and learns computational tasks at a cellular level.
“We’re interested in studying how brains compute,” said DeMarse.
“If you think about your brain, and learning and the memory process, I can ask you questions about when you were five-years-old and you can retrieve information. That’s a tremendous capacity for memory. In fact, you perform fairly simple tasks that you would think a computer would easily be able to accomplish, but in fact it can’t.”
Although computers can perform certain tasks extremely quickly, they lack the flexibility and adaptability of the human brain and perform particularly poorly at pattern recognition tasks.
“If we extract the rules of how these neural networks are doing computations like pattern recognition we can apply that to create novel computing systems,” said DeMarse.
“There’s a lot of data out there that will tell you that the computation that’s going on here isn’t based on just one neuron. The computational property is actually an emergent property of hundreds of thousands of neurons cooperating to produce the amazing processing power of the brain.”
As well as enhancing scientific knowledge of how the brain works, the neurons may provide clues to brain dysfunction. For example, an epileptic seizure is triggered when all the neurons in the brain fire simultaneously — a pattern commonly replicated by a neural network in a dish.
When linked up to an F-22 jet flight simulator, the brain and the simulator established a two-way connection similar to how neurons receive and interpret signals from each other to control our bodies.
Gradually the brain learnt to control the flight of the plane based on the information it received about flight conditions.
However, the brain still falls a long way short of the complexity of the human brain, which has billions of neurons, and Steven Potter, a biomedical engineer at the Georgia Institute of Technology, said a brain in a dish flying a real plane was still a long way off.
“A lot of people have been interested in what changes in the brains of animals and people when they are learning things,” said Potter, DeMarse’s former supervisor.
“We’re interested in getting down into the network and cellular mechanisms, which is hard to do in living animals. And the engineering goal would be to get ideas from this system about how brains compute and process information.”