Mushrooms are renowned for their resilience and unique biological properties, which make them a compelling choice for the field of bioelectronics. This cutting-edge area merges biology and technology to create innovative and sustainable materials that could shape the future of computing systems.
Researchers at The Ohio State University have made groundbreaking discoveries regarding edible fungi, particularly shiitake mushrooms. These fungi can be cultivated to function as organic memristors—components that emulate memory cells capable of retaining information regarding previous electrical states. The experiments revealed that these mushroom-based devices could replicate the same memory behaviors typically observed in traditional semiconductor chips.
John LaRocco, the lead author of the study and a research scientist at Ohio State's College of Medicine, explained, "Developing microchips that imitate actual neural activity allows for reduced power consumption during standby or idle times, offering significant computational and economic advantages."
While the concept of fungal electronics is not entirely new, it is gaining traction as a practical solution for sustainable computing. Fungal materials are not only biodegradable but also cost-effective to produce, making them an excellent alternative to conventional semiconductors, which often rely on rare minerals and consume large amounts of energy.
LaRocco emphasized, "Our research aims to push the boundaries of memristive systems, exploring the potential of mycelium as a computing substrate in innovative ways." Their findings were documented and published in the journal PLOS One.
To gauge the capabilities of these fungi, researchers cultivated samples of shiitake and button mushrooms. Once fully matured, the mushrooms were dehydrated for preservation and connected to custom electronic circuits. The team exposed the mushrooms to controlled electric currents at varying voltages and frequencies.
"We connected electrical wires and probes to different parts of the mushrooms, as each section exhibits unique electrical properties," said LaRocco. "By adjusting the voltage and connectivity, we observed varying performances."
After two months of rigorous testing, researchers found that their mushroom-based memristor could switch between electrical states an impressive 5,850 times per second with approximately 90% accuracy. Although performance declined at higher electrical frequencies, they discovered that interconnecting multiple mushrooms could restore stability, akin to the neural connections found in the human brain.
Qudsia Tahmina, a co-author of the study and an associate professor of electrical and computer engineering at Ohio State, remarked, "These results demonstrate the adaptability of mushrooms for computing applications. Growing societal awareness about environmental conservation could drive the development of bio-friendly solutions like this."
Although organic memristors are still in their infancy, researchers are eager to refine cultivation techniques and miniaturize device sizes in future projects. Creating smaller and more efficient fungal components will be crucial for establishing them as viable alternatives to traditional microchips.
LaRocco noted, "Exploring the intersection of fungi and computing can range from something as simple as a compost heap with homemade electronics to larger-scale culturing factories with pre-made templates. All these approaches are feasible with the resources currently available."
Other contributors to the study from Ohio State include Ruben Petreaca, John Simonis, and Justin Hill. The research received support from the Honda Research Institute, underscoring the collaborative efforts to harness the potential of mushrooms in the realm of bioelectronics.
