Bog'liq Kurzweil, Ray - Singularity Is Near, The (hardback ed) [v1.3]
Other Works in Progress: An Artificial Hippocampus and an Artificial Olivocerebellar Region The hippocampus is vital for learning new information and long-term storage of memories. Ted Berger and his
colleagues at the University of Southern California mapped the signal patterns of this region by stimulating slices of
rat hippocampus with electrical signals millions of times to determine which input produced a corresponding output.
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They then developed a real-time mathematical model of the transformations performed by layers of the hippocampus
and programmed the model onto a chip.
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Their plan is to test the chip in animals by first disabling the corresponding
hippocampus region, noting the resulting memory failure, and then determining whether that mental function can be
restored by installing their hippocampal chip in place of the disabled region.
Ultimately, this approach could be used to replace the hippocampus in patients affected by strokes, epilepsy, or
Alzheimer's disease. The chip would be located on a patient's skull, rather than inside the brain, and would
communicate with the brain via two arrays of electrodes, placed on either side of the damaged hippocampal section.
One would record the electrical activity coming from the rest of the brain, while the other would send the necessary
instructions back to the brain.
Another brain region being modeled and simulated is the olivocerebellar region, which is responsible for balance
and coordinating the movement of limbs. The goal of the international research group involved in this effort is to apply
their artificial olivocerebellar circuit to military robots as well as to robots that could assist the disabled.
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One of their
reasons for selecting this particular brain region was that "it's present in all vertebrates—it's very much the same from
the most simple to the most complex brains," explains Rodolfo Llinas, one of the researchers and a neuroscientist at
New York University Medical School. "The assumption is that it is conserved [in evolution] because it embodies a
very intelligent solution. As the system is involved in motor coordination—and we want to have a machine that has
sophisticated motor control—then the choice [of the circuit to mimic] was easy."
One of the unique aspects of their simulator is that it uses analog circuits. Similar to Mead's pioneering work on
analog emulation of brain regions, the researchers found substantially greater performance with far fewer components
by using transistors in their native analog mode.
One of the team's researchers, Ferdinando Mussa-Ivaldi, a neuroscientist at Northwestern University, commented
on the applications of an artificial olivocerebellar circuit for the disabled: "Think of a paralyzed patient. It is possible
to imagine that many ordinary tasks—such as getting a glass of water, dressing, undressing, transferring to a
wheelchair—could be carried out by robotic assistants, thus providing the patient with more independence."