Sunday, January 19, 2020

"Towards fungal computer"

Via The National Center for Biotechnology Information, The Royal Society's Interface Focus:
Abstract
We propose that fungi Basidiomycetes can be used as computing devices: information is represented by spikes of electrical activity, a computation is implemented in a mycelium network and an interface is realized via fruit bodies. In a series of scoping experiments, we demonstrate that electrical activity recorded on fruits might act as a reliable indicator of the fungi’s response to thermal and chemical stimulation. A stimulation of a fruit is reflected in changes of electrical activity of other fruits of a cluster, i.e. there is distant information transfer between fungal fruit bodies. In an automaton model of a fungal computer, we show how to implement computation with fungi and demonstrate that a structure of logical functions computed is determined by mycelium geometry.
Keywords: natural computation, fungi, unconventional computing
1. Introduction
The fungi are the largest, widely distributed and oldest group of living organisms []. The smallest fungi are microscopic single cells. The largest mycelium belongs to Armillaria bulbosa, which occupies 15 hectares and weights 10 tons [], and the largest fruit body belongs to Fomitiporia ellipsoidea, which at 20 years old is 11 m long, 80 cm wide, 5 cm thick and has an estimated weight of nearly half-a-ton []. During the last decade, we produced nearly 40 prototypes of sensing and computing devices from the slime mould Physarum polycephalum [], including the shortest path finders, computational geometry processors, hybrid electronic devices, see the compilation of the latest results in []. 

 We found that the slime mould is a convenient substrate for unconventional computing; however, the geometry of the slime mould’s protoplasmic networks is continuously changing, thus preventing fabrication of long-living devices, and slime mould computing devices are confined to experimental laboratory set-ups. Fungi Basidiomycetes are now taxonomically distinct from the slime mould; however, their development and behaviour are phenomenologically similar: mycelium networks are analogous to the slime mould’s protoplasmic networks, and the fruit bodies are analogous to the slime mould’s stalks of sporangia. Basidiomycetes are less susceptible to infections; when cultured indoors, especially commercially available species, they are larger in size and more convenient to manipulate than slime mould, and they could be easily found and experimented on outdoors. This makes the fungi an ideal object for developing future living computing devices. 

Advancing our recent results on electrical signalling in fungi [], which in a way is similar to electrical signalling in plants [], we are exploring the computing potential of fungi in the present paper. We introduce a mycelium basis of fungal computing and define an architecture of fungal computers in §2. Findings on the electrical activity of fungi [,,] are augmented in §3 by demonstrations of endogenous spiking, signalling between fruit bodies and signalling by fruit bodies about the state of the growth substrate. In experiments, we use oyster mushrooms, species pleurotus, family Tricholomataceae, because of their wide availability and interesting properties []. We imitate electrical activity of the mycelium in a discrete model in §4. There we encode logical values into presence/absence of spikes in fruit bodies and show how logical functions can be executed. We also demonstrate that a geometrical structure of mycelium, in the model this is represented by a random planar set structure, affects families of logical circuits computed. Directions of future research on fungal computing are outlined in §5....

I'm thinking mushroom omelette.
 
Meanwhile at engadget: 

Hitting the Books: Teaching AI to sing slime mold serenades
Get ready for Mozart on a microchip.
What will be the central processing unit of the future? —Eduardo Miranda
Eduardo Miranda wants to shake up musical composition. At the moment, he is interested in central processing units (CPUs). In today's computers, CPUs are silicon chips with circuitry that enables them to perform arithmetical, logical, and control operations. But supposing we go beyond silicon, beyond digital, beyond even a quantum computer? What about, for example, a bioprocessor that powers a biocomputer? Or a hybrid computer, powered by silicon plus a bioprocessor?

A bioprocessor processes biological material. Miranda's chosen bioprocessor is a slime mold called Physarum polycephalum, the "many-headed slime," a huge, yellow, single-cell organism packed with millions of nuclei. It is a mass of creeping, jelly-like protoplasm that is sensitive to light and spreads out over forest floors, eating fungal spores, bacteria, and microbes.

Physarum polycephalum has extraordinary electrical properties. Passing an electrical current through it makes it behave like an electronic component called a memristor. Memristors have a memory for current; their electrical resistance depends on the amount of current that has passed through them in the past. For Miranda, the most interesting thing about biological memristors is that they are not as precise as silicon-based digital ones. The mold's electrical output is related to the input but in ways that can be hard to predict. He considers it a "creative processor." Turn the pitch of a sound into electrical impulses and the slime mold will produce its own electrical response, which can then be turned back into music.

Miranda plays duets with the slime mold, which responds with enigmatic sounds produced on his piano. The piano is the interface between himself and his biocomputer. He entitled the first piece that emerged "Biocomputer Music: A Composition for Piano and Biocomputer."...  MORE