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Updated: Mar 23, 2026

A Method for Growing Bio-memristors from Slime Mold
Published on: November 2, 2017
On hybrid circuits exploiting thermistive properties of slime mould
Xavier Alexis Walter1,2, Ian Horsfield2, Richard Mayne1
1Unconventional Computing Center, University of the West of England, Bristol, BS16 1QY, United Kingdom.
Abstract:
Slime mould Physarum polycephalum is a single cell visible by the unaided eye. Let the slime mould span two electrodes with a single protoplasmic tube: if the tube is heated to approximately ≈40 °C, the electrical resistance of the protoplasmic tube increases from ≈3 MΩ to ≈10,000 MΩ. The organism's resistance is not proportional nor correlated to the temperature of its environment. Slime mould can therefore not be considered as a thermistor but rather as a thermic switch. We employ the P. polycephalum thermic switch to prototype hybrid electrical analog summator, NAND gates, and cascade the gates into Flip-Flop latch. Computing operations performed on this bio-hybrid computing circuitry feature high repeatability, reproducibility and comparably low propagation delays.
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