In a study published by the University of Southampton this week, it has been demonstrated that biological neurons, cultured from rats, can pass information through a physical synapse-like element to artificial neurons and vice versa. All three elements of the study; artificial neurons, biological neurons and the synapse component were in different locations across the world, connected by the web.

In recent years, there has been huge efforts across the world to move forward with the technology of neuroelectronic links which would forge connections between our minds and the internet. Such systems would potentially allow our brains to interact with data in real time, just like we do with our own knowledge, thoughts and memories.

Elon Musk’s company Neuralink is heavily invested in developing this concept, proposing implantation of a tiny device into the brain which would connect us directly to the internet.

Biology

In nature, the brain functions through a huge network of neurons which send information to other neurons via electrical signals, individually referred to as an ‘action potential’. The space between neurons, over which this signal travels, is called a synapse.

Neurons are only capable of sending information in one direction. A signal will travel through one neuron, to its outgoing end. The information passes across the synapse and stimulates the next neuron at it’s receiving end, and so on.

Figure adapted from Khan Academy and Original Research Paper (Serb, A., Corna, A., George, R. et al. Memristive synapses connect brain and silicon spiking neurons. Sci Rep 10, 2590 (2020). https://doi.org/10.1038/s41598-020-58831-9)

Silicon

The study was comprised of three interacting components. The biological neurons were cultured from rats and organised on to an electrode array at the University of Zurich and ETH Zurich. Through well established laboratory techniques, electrical signals from these neurons can be sent, and receiving signals captured.

The artificial neurons were developed at the University of Padova, Italy and arranged on to silicon microchips. Much like biological neurons, they are capable of sending and receiving signals that can be read and measured.

At the University of Southampton, scientists used memristors, tiny circuit components capable of relaying electronic charge, to create physical devices that act to transfer information from biological neurons to artificial, and also the reverse. The resultant artificial synapse was termed a synpator.

Due to differences in input and output between the neurons, two separate synaptors were created to complete the circuit, one representing brain-to-silicon and one silicon-to-brain.

The slight differences in cutting edge nanotechnology used within the two synaptors resulted in a unidirectional circuit. In this sense, the system mimics the brain, with information only able to pass through it’s respective system in one direction.

The teams were able to successfully relay electronic signals across all elements of the study, using the internet. This is the first time that artificial and biological components have been linked in such a way, across different locations.

The results are hugely significant in the world of neural interfaces research, and will most likely influence many other areas of study. Scientists behind the work have noted that they hope this could be the start of an internet of neuroelectronics (Reported by ScienceDaily).

This article was originally published by Ellie harris on medium.