New Scientist reports on a cool, if somewhat creepy development in robotics -- scientists have used bits from a rat's brain to control a robot. The 'why' behind such a Frankenstein is to learn more about how a brain works: by studying the rat brain's reponses to controlled stimulus, the scientists hope to learn more about the internal workings of a brain, which will go a long way to understand the nature of human brain disorders such as Alzheimer's.

Now for the 'how' -- a rat's neural cortex, the stuff that will eventually form the brain, is removed from the fetus and constituent neurons are seperated from each other. This neuron soup, if you will, is then applied to a bank of electrodes and is fed via a neutrient-rich medium. With time, the neurons reach out and reconnect with each other, forming a mesh of rudimentary brain tissue. Pretty soon, the axons and dendrites are firing and the neurons are chemically talking to each other. This entire setup is kept in a box, about the size of a microwave. The box then wirelessly communicates with a mechanical robot via Bluetooth.



The idea is: if they can get this brain-robot to respond to stimulus, and respond in a controllable manner, then the scientists would change the brain matter -- chemically, electically, or biologically, to find out how the controlled responses change. This feedback mechanism, the scientists hope, would help shed light on how a brain functions. An example of a stimulus could be a wall obstruction that the mechanical robot would need to evade. The presence of this wall would then act as a stimulus to the rat brain tissues, which would fire off in a repeatable manner -- their response to the stimulus. The robot would in turn be fed electrical signals based on the fixed brain-reponse; electrical signals then used to steer the robot left or right to avoid the wall.

You can read more about this rat-machine complex here

Source: New Scientist via Slashdot