Scientists have developed an artificial neuron that operates at the same voltage as real nerve cells. This breakthrough helps bridge the gap between technology and biology, allowing devices to communicate with living cells more naturally.
Inside a lab at the University of Massachusetts Amherst, researchers, led by Jun Yao, created this artificial neuron to produce electrical spikes around 0.1 volts. This closely resembles the firing patterns of natural neurons. Previously, artificial neurons needed much higher voltages, making it challenging to interact directly with biological cells. By matching the voltage range of real neurons, researchers have opened doors to new possibilities in bio-inspired technology.
Why does voltage matter? Living neurons typically fire between 70 and 130 millivolts. In contrast, earlier artificial versions required at least 0.5 volts. According to Yao, older models consumed ten times more power, which hindered their ability to connect with living tissue. The new design addresses these energy concerns while paving the way for practical applications.
At the core of the artificial neuron is a memristor, a tiny component that adjusts its resistance based on current. This innovative element is enhanced with bacterial protein nanowires from Geobacter sulfurreducens, a microbe known for its ability to transfer electrons. These nanowires help the device operate at biological voltage levels, mimicking the electrical behavior of real neural spikes.
Chemical factors also play a role in how these artificial neurons fire. For instance, when sodium levels increase, the circuit resets more quickly, leading to more frequent firings. Similarly, dopamine influences activity in a complex way, responding differently at various concentrations. This dynamic mimics how living brains respond to chemical signals.
To further evaluate the artificial neuron, the team connected it to heart muscle cells. Normal heart activity kept the neuron quiet, but when the heart’s rhythm increased due to a drug, the artificial neuron responded with electrical spikes. While this doesn’t establish a direct connection to human brain function, it shows the potential for real-time communication with living cells.
Today’s wearable health devices often amplify faint biological signals, requiring more energy and complex hardware. Yao’s team suggests that with this low-voltage neuron, devices could operate without needing that amplification, leading to smaller and more efficient sensors.
The exciting aspect of this work is not just one standout feature, but a cohesive match between electronic and biological functions. Earlier devices often missed the finer details of natural neural behavior, but this innovation aligns on multiple levels: voltage, energy use, timing, and chemical interaction.
Research is ongoing. Future developments depend on enhancing sensor technology and further testing in living nervous tissue. There’s optimism, though—the boundaries between artificial devices and biological systems are becoming more flexible. This research was published in Nature Communications.
As technology evolves, the prospect of seamless interaction between man-made devices and living organisms becomes more tangible than ever.
