A crew at the University of Massachusetts Amherst has found, while on their way to better understanding protein nanowires, how to use these biological, electricity conducting filaments to make a neuromorphic memristor, or “memory transistor,” system. It fucntioons extremely efficiently on very low power, as brains do, to carry alerts between neurons. Details are available in Nature Communications.
As the lead writer Tianda Fu, a Ph.D. candidate in electrical and computer engineering, explains, one of the greatest challenges to neuromorphic computing, and one that made it appear unreachable, is that most conventional computer systems operate at over 1 volt, while the mind sends signals called action potentials between neurons at around 80 millivolts—many times lower.
At present, a decade after early experiments, memristor voltage has been achieved in the range similar to standard computer, however getting below that seemed unbelievable, he adds.
Fu reports that utilizing protein nanowires created at UMass Amherst from the bacterium Geobacter by microbiologist and co-author Derek Lovely. He has now performed experiments where memristors have reached neurological voltages. Those assessments had been conducted in the lab of electrical and computer engineering researcher and co-author Jun Yao.
Lovely points out that Geobacter’s electrically conductive protein nanowires offer many benefits over expensive silicon nanowires, which require toxic chemical compounds and high-energy processes to produce.
They used a metal thread because protein nanowires facilitate metal reduction, changing metal ion reactivity and electron transfer properties. Lovely says this microbial capability isn’t a surprise, because wild bacterial nanowires breathe and chemically scale down metals to get their energy the way humans breathe oxygen.