We are tackling global challenges through our research, collaborating with academic and industrial partners to deliver environmental, societal and economic impact. Below are examples of this.
Successfully reproducing the electrical properties of biological neurons onto semiconductor chips
In 2019, we made headlines around the world when our physicists reported a first-of-its-kind achievement – successfully reproducing the electrical properties of biological neurons onto semiconductor chips.
These artificial neurons behave just like the real thing and have enormous scope for medical devices to cure chronic diseases, such as heart failure, Alzheimer’s and other diseases of neuronal degeneration. The ‘neurons’ only need one-billionth the power of a microprocessor, making them ideally suited for use in medical implants and bio-electronic devices.
The research team was led from Bath. Researchers from the Universities of Bristol, Zurich and Auckland also participated.
Designing artificial neurons that respond properly to signals from the nervous system has been a major goal in medicine for decades, as it opens up the possibility of curing conditions where neurons don’t work correctly. In heart failure, for example, neurons in the base of the brain don’t respond properly to nervous system feedback. In turn, they don’t send the right signals to the heart, resulting in the heart not pumping as effectively as it should.
Overcoming the challenges
Despite the potential of artificial neurons, developing them has been immensely challenging due to the biological complexity and hard-to-predict neuronal responses.
The researchers successfully modelled and derived equations to explain how neurons respond to electrical stimuli from other nerves. This is complicated as responses are ‘non-linear’. In other words, if a signal becomes twice as strong, it doesn’t necessarily elicit twice as big a reaction – the response might be three times bigger, or something else.
The team designed silicon chips that accurately modelled biological ion channels and went on to prove that these silicon neurons precisely mimicked real, living neurons responding to a range of stimulations.
The researchers accurately replicated the complete dynamics of hippocampal neurons and respiratory neurons from rats, under a wide range of stimuli. Professor Alain Nogaret, from the Department of Physics, led the project.
“Until now, neurons have been like black boxes, but we have managed to open the black box and peer inside. Our work is paradigm-changing because it provides a robust method to reproduce the electrical properties of real neurons in minute detail. But it’s wider than that because our neurons only need 140 nanoWatts of power; a billionth the power requirement of a microprocessor. This makes the neurons well suited for bio-electronic implants to treat chronic diseases. For example, we’re developing smart pacemakers that will use these neurons to respond in real time to demands placed on the heart – which is what happens in a healthy heart.”
The study was funded by a European Union Horizon 2020 Future Emerging Technologies Programme grant and a doctoral studentship from the Engineering and Physical Sciences Research Council.