Brain cells fly F-22 simulator

By David Yip
2B Mechanical

How many rats does it take to fly an F-22 Raptor? Well, not even one. About 25 000 rat brain cells will do the trick. Thomas deMarse, a professor of biomedical engineering at the University of Florida, has managed to grow a living “brain” that can fly a F-22 simulator through a computer interface. This gives researchers an opportunity to actually see the neurons connect to each other and learn.

When the neurons are first put in the dish, they look like grains of sand in water. However, as the brain learns, microscopic lines begin to extend from one grain to another, that representing the learning of processes. “You see one extend a process, pull it back, extend it out – and it may do that a couple of times, just sampling who’s next to it, until over time the connectivity starts to establish itself,” deMarse says, “(The brain is) getting its network to the point where it’s a live computation device.”

The brain interacts with the F-22 simulator through an array of 60 electrodes that sit under the brain culture. The electrodes are then connected through a standard desktop computer, and then to the simulator. Live brain cells are then placed on the culture, which then begin to reconnect themselves, forming a neural network. It takes about 15 minutes for the network to adjust to flying the plane.

To control the simulator, the brain receives information from the computer about the current flight conditions, such as the degree of pitch and roll. Information is transmitted to the brain by sending signals to electrodes which can stimulate different parts of the culture. The brain analyzes the incoming information, and adjusts by sending signals back through the electrode plate to the computer and the simulator’s controls. The simulator reacts, and sends information back to the brain, creating feedback loop.

“Initially when we hook up this brain to a flight simulator, it doesn’t know how to control the aircraft,” deMarse said. “So you hook it up and the aircraft simply drifts randomly. And as the data comes in, it slowly modifies the (neural) network so over time, the network gradually learns to fly the aircraft.” deMarse plans to make the autopilot more competent by having the brain use a horizon to judge how it controls the plane.

At the moment the brain can control the pitch and roll of the plane, in weather from calm skies to hurricane winds. However, the fundamental goal of the project is to understand how individual neurons interact in a network, and hopefully shed light on neural disorders such as epilepsy.
“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 5 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.” While computers are very fast at processing some kinds of information, they can’t approach the flexibility of the human brain, DeMarse said. In particular, brains can easily make certain kinds of computations – such as recognizing an unfamiliar piece of furniture as a table or a lamp – that are very difficult to program into today’s computers. “If we can extract the rules of how these neural networks are doing computations like pattern recognition, we can apply that to create novel computing systems,” he said. “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 or thousands of neurons cooperating to produce the amazing processing power of the brain.”

The ultimate goal is to create a mathematical model emulates how neurons compute. Before this can happen, connections between neurons must be understood. MRI scans show millions of neurons firing together. At that resolution, it is impossible to see what's happening between individual neurons. While scientists can study neural activities from groups of cells in a dish, they can't watch them learn and grow as they would within a living body unless the neurons have some kind of body to interact with; this is where the simulator comes in, standing in for an actual body.

The brain-in-a-dish may also have applications in handling tasks that are extremely dangerous, such as search and rescue, or bomb damage assessments. As living computers, they may someday be used to fly small unmanned airplanes or handle tasks that are dangerous for humans, such as search-and-rescue missions or bomb damage assessments.

Those of you who have seen the movie Macross Plus may hearken back to the experimental brainwave control system and interface used to fly the fictional YF-21 mecha. Maybe not so far off now? Or maybe they can hook me up to an electrode plate, and stimulate parts of me to help my learn calculus, without actually me knowing. Eh? “I know kung-fu!”

Files from the University of Florida, and Discovery Channel.