Researchers from the RMIT University were inspired by an emerging tool in biotechnology, called optogenetics, to develop a device that replicates the way the brain stores and loses information.
As reported, the new chip is based on an ultra-thin material that changes electrical resistance in response to different wavelengths of light.
This enables the chip to mimic the way neurons work to store and delete information in the brain.
According to the research team leader, the technology makes it possible to move closer towards artificial intelligence (AI) that can harness the brain’s full sophisticated functionality.
Optogenetics allows scientists to delve into the body’s electrical system with incredible precision, using light to manipulate neurons so that they can be turned on or off.
Imitating the brain
The optogenetically-inspired chip imitates the fundamental biology of nature’s best computer, which is the human brain.
Being able to store, delete and process information is critical for computing, and the brain does this extremely efficiently.
The team was able to simulate the brain’s neural approach simply by shining different colours onto the chip.
Benefits of the chip
This technology has taken them further on the path towards fast, efficient and secure light-based computing.
Additionally, it brings them a step closer to the realisation of a bionic brain, or a brain-on-a-chip, that can learn from its environment just like humans do.
Dr Taimur Ahmed, the lead author of the study published in Advanced Functional Materials, explained that being able to replicate neural behaviour on an artificial chip offered exciting avenues for research across sectors.
For one, it will provide tremendous opportunities for researchers to better understand the brain and how it is affected by disorders that disrupt neural connections, like Alzheimer’s disease and dementia.
The researchers, from the Functional Materials and Microsystems Research Group at the University, have also demonstrated the chip can perform logic operations such as information processing, which is another brain-like functionality.
Developed at the Micro Nano Research Facility, the technology is compatible with existing electronics and has also been demonstrated on a flexible platform, for integration into wearable electronics.
How the chip works
Neural connections happen in the brain through electrical impulses. When tiny energy spikes reach a certain threshold of voltage, the neurons bind together, thus creating a memory.
On the chip, light is used to generate a photocurrent. Switching between colours causes the current to reverse direction from positive to negative.
This direction switch, or polarity shift, is equivalent to the binding and breaking of neural connections.
This is a mechanism that enables neurons to connect and induce learning, or inhibit and induce forgetting.
This is akin to optogenetics, where light-induced modification of neurons causes them to turn on or off, enabling or inhibiting connections to the next neuron in the chain.
To develop the technology, the researchers used material called black phosphorus (BP), which can be inherently defective in nature.
This is usually a problem for optoelectronics, but with precision engineering the researchers were able to harness the defects to create new functionality.