- One day your brain could live on in a mechanical shell
- The advent of "cyborgs" has been brought a
step closer by the creation of a strange hybrid creature with a mechanical
body controlled by the brain of a fish. As ghoulish as this chimera sounds,
it may one day allow people to be fitted with prosthetic devices that are
controlled directly by their brain.
- Light sensors housed in the mechanical body feed the
brain sensory information. The brain tissue processes this information
to generate command signals which tell the robot's motors which way to
turn in response to its environment. Steve Grand, a expert in artificial
life with Cyberlife Research in Somerset, describes the work as "laudably
perverse" and likely to bring the world of cyborgs one step closer.
- The robot possesses only a few neurons borrowed from
the sea lamprey Petromyzon marinus, a primitive eel-like vertebrate. Yet
it still displays apparently "complex" behaviours in response
to simple light stimuli. Ferdinando Mussa-Ivaldi of Northwestern University
in Chicago and his colleagues at the University of Illinois also in Chicago
and the University of Genoa, Italy, describe it as an "artificial
- To create the hybrid, the team extracted a lamprey's
brainstem and part of its spinal cord under total anaesthetic, and maintained
it in an oxygenated and refrigerated salt solution. The researchers then
located a group of a few very large nerve cells known as Müller cells.
These cells, which are easy to access and have been extensively studied,
are responsible for integrating command and sensory signals directed to
the motor nerves, helping the lamprey orient itelf.
- Mussa-Ivaldi and his colleagues then attached electrodes
to stimulate the Müller cells with the sorts of frequencies they would
normally receive. Other electrodes monitored the activity at the axons,
the output part of the neurons.
- The robot itself is a commercially available module called
a Khepera and couldn't look less like a lamprey. With two wheels and a
body made up of a couple of circular circuit boards it looks more like
a wired-up Oreo biscuit than a cyborg. The researchers didn't mount the
brain tissue on the robot, but connected it by wire.
- When the robot was presented with a number of light stimuli,
its lamprey brain responded with a variety of behaviours, such as following
the light, avoiding the light and moving in a circle.
- The research was originally intended to explore how brain
cells adapt to changing stimuli. But Mussa-Ivaldi hopes that learning how
neurons can communicate with artificial machines will have other benefits.
"We will be able to build better prosthetic limbs and devices for
disabled people," he says.
- Team member Vittorio Sanguineti of the University of
Genoa says the work can also reveal the principles of how the brain learns
and how memory works. The work will be presented at Artificial Life 7 in
Portland, Oregon, in August.
- Kevin Warwick, a cyberneticist at Reading University,
believes that it may even one day be possible to have your brain transferred
to a robot when your body dies. It would be extremely difficult, "but
mapping the entire brain to a robot can't be ruled out", he says.
More realistic, he says, is connecting electronic devices such as mobile
phones directly into our brains.
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