Are there man-made organic computers?

We now have memristors made from fungal mycelium. Fungal electronics has been explored before, but this newer work uses shiitake mycelium grown into a usable form, then dried so the material is easier to control. In the study, researchers applied electrical signals to different points in the network and were able to switch between electrical states up to 5.85 kHz, with about 90% accuracy.

Memristors are interesting because they do not just conduct current; their resistance depends on the history of the electrical signals that have passed through them. In that sense, they “remember” what happened before, and that memory can remain even when the power is switched off. That is what makes them useful as a kind of memory component, not just a wire or resistor.

The authors also suggest that this kind of fungal system could be scaled up, even to the size of compost heaps, which could dramatically increase its computational potential. Because fungal mycelium naturally grows into large interconnected networks, scaling up the technology may be easier than with many conventional electronic materials.

This is still very early-stage research, so it is not something you are going to find inside household electronics anytime soon. But the point is clear enough: fungal mycelium may turn out to be a practical material for certain computing tasks, especially where a biodegradable and environmentally friendly alternative to conventional electronics would be useful.