Ohio State University researchers realize they're not high after turning shiitake mushrooms into memory cells

Researchers at Ohio State University have turned shiitake mushrooms into memory cells when controlled by an Arduino microcontroller board. The study was funded in part by the Honda Research Institute.

The researchers first grew four large shiitake mushrooms from spores within a culture optimized for rapid growth. Next, they dehydrated the mushrooms into round discs after seven days of direct sunlight.

An Arduino UNO microcontroller board with a few simple wires, resistors, and other parts was used to create a simple voltage test memory circuit. The researchers leveraged the ability of the conductive mycelium networks within the porous structure of fungi to conduct and store electrical charges necessary use them as memristors, or non-volatile memory cells. Testing began once two mushrooms were connected and rehydrated with a brief mist of aerosolized deionized water to activate their memristor properties.

The Arduino board was first used to feed square or sine wave voltages into the mushrooms while their state was read out at 56k baud. Depending on the waveform type, voltage, frequency, and other factors, the accuracy of the readout ranged from 46 to 95-percent, with a 10Hz 5V sine wave producing the best results. Then, single read/write operations were tested, with results ranging from 88 to 96-percent.

These fungal memristors produce far less waste than traditional silicon-based memory and can be disposed of without introducing toxic waste into public dumps. The system was studied for less than two months, so the longevity of data stored within mushrooms is still unknown.

Readers interested in trying their hand at building their own shiitake mushroom storage device at home can pick up an Arduino UNO R4 and a pack of dried shiitake mushrooms from Amazon. Trekkies interested in another use of mycelium networks can watch Star Trek: Discovery to see the use of the Spore Drive.