Honey may be used in computer chips that work like brain cells

Modern computers may seem capable of phenomenal and awe-inspiring feats of processing, but they have nothing on the human brain. With its 100 billion neurons and more than 1,000 trillion synapses or neuronal connections, the human brain is much more efficient than a traditional computer. In fact, computers that mimic the way in which human brains function may well be next, in terms of hardware development. 

Currently, conventional computer systems are based on what is called the von Neumann architecture. They consist of an input, usually from a keyboard and mouse, and an output, such as to a monitor. They also involve a CPU, or central processing unit, and RAM, or memory storage. Transferring data through all these mechanisms from input to processing to memory to output takes a lot of power, at least compared to the human brain. 

For instance, the Fugaku supercomputer uses upwards of 28 megawatts, roughly equivalent to 28 million watts, to run while the brain uses only around 10 to 20 watts. In addition, this conventional computer architecture does not allow for an instruction fetch and a data operation to take place at the same time, as both transfers of information share a common bus. This is referred to as the von Neumann bottleneck, and it can limit the performance of the system. In contrast, human brain neurons can both process and store data, which makes them more efficient.

Computer engineers are now trying to design computing systems that mimic the way neurons and synapses work in the human brain. They are developing components for these neuromorphic systems and are trying to do so in environmentally friendly ways. Hailed by some as the future of computing, neuromorphic systems are much faster and use much less power than traditional computers. 

In a recent study, engineers at Washington State University have demonstrated how to make an environmentally friendly memristor, a component similar to a transistor that can not only process but also store data in memory. One of the important components of the memristor is a thin layer of solid honey layered between two metal electrodes. 

“This is a very small device with a simple structure, but it has very similar functionalities to a human neuron,” said Feng Zhao, associate professor of WSU’s School of Engineering and Computer Science, and corresponding author on the study. “This means if we can integrate millions or billions of these honey memristors together, then they can be made into a neuromorphic system that functions much like a human brain.”

For the study, Zhao and first author Brandon Sueoka, a WSU graduate student in Zhao’s lab, created memristors by processing honey into a solid form and sandwiching it between two metal electrodes, making a structure similar to a human synapse. They then tested the honey memristors’ ability to mimic the work of synapses with high switching on and off speeds of 100 and 500 nanoseconds respectively. The memristors also emulated the synapse functions known as spike-timing dependent plasticity and spike-rate dependent plasticity, which are responsible for learning processes in human brains and for retaining new information in neurons.

Currently the memristors have been developed at the micro scale, and so are approximately the size of a human hair. Zhao plans to make further changes in future, so that these components are sized at the nano scale and are comparable to about 1/1,000 of a human hair. In this case, many millions or even billions of these components could be bundled together, just like neurons in a nerve, to make a full neuromorphic computing system.

Several companies, including Intel and IBM, have already released neuromorphic chips which have the equivalent of more than 100 million “neurons” per chip; this may sound impressive, but it is not yet near the number of these structures found in the brain. 

In developing the memristors, Zhao and his team have focused on looking for biodegradable materials to use in order to address the current ecological challenges of electronic waste. While many developers are still using the same nonrenewable and toxic materials that are currently used in conventional computer chips, Zhao’s investigations have led him to test various proteins, as well as the sugars in honey and in Aloe vera leaves for use in the memristors.  He has found that honey has great potential for this task. 

“Honey does not spoil,” he said. “It has a very low moisture concentration, so bacteria cannot survive in it. This means these computer chips will be very stable and reliable for a very long time.”

The honey memristor chips developed at WSU should tolerate the lower levels of heat generated by neuromorphic systems which do not get as hot as traditional computers. The honey memristors will also cut down on electronic waste.

“When we want to dispose of devices using computer chips made of honey, we can easily dissolve them in water,” said Professor Zhao. “Because of these special properties, honey is very useful for creating renewable and biodegradable neuromorphic systems.”

The study is published in the Journal of Physics D.

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By Alison Bosman, Earth.com Staff Writer