The real time monitoring of brain function has advanced in leaps and bounds in recent years. That’s largely thanks to various new technologies that can monitor the collective behaviour of groups of neurons, such as functional magnetic resonance imaging, magnetoencephalopathy and positron emission tomography.
This work is revolutionising our understanding of the way the brain is structured and behaves. It has also lead to a new engineering discipline of brain-machine interfaces, which allows people to control machines by thought alone.
Impressive though these techniques are, they all suffer from inherent limitations such as limited spatial resolution, a lack of portability and extreme invasiveness.
Today, Dongjin Seo and pals at the University of California Berkeley reveal an entirely new way to study and interact with the brain. Their idea is to sprinkle electronic sensors the size of dust particles into the cortex and to interrogate them remotely using ultrasound. The ultrasound also powers this so-called neural dust.
Each particle of neural dust consists of standard CMOS circuits and sensors that measure the electrical activity in neurons nearby. This is coupled to a piezoelectric material that converts ultra-high-frequency sound waves into electrical signals and vice versa.