SMALLER than a grain of salt yet more powerful than ever imagined, a neural implant has been shown to wirelessly record brain activity in living animals for more than a year, marking a major milestone in neurotechnology and bioengineering.
Breakthrough Miniaturisation in Neural Implant Design
Researchers at Cornell University and Nanyang Technological University have created a neural implant so compact it measures just 300 microns long and 70 microns wide. Researchers sought to demonstrate the functional microelectronic systems can now be built at an unprecedentedly small scale, opening the door to advanced neural monitoring and integrated biomedical sensing. The device, known as a microscale optoelectronic tetherless electrode, or MOTE, represents a new class of bio-compatible tools capable of long-term, wireless data transmission.
How the MOTE Works and What It Reveals
The neural implant uses red and infrared laser beams that harmlessly pass through brain tissue to power the device. A semiconductor diode made of aluminium gallium arsenide both captures this light energy and emits infrared signals to relay brain data. With its built-in low-noise amplifier and optical encoder, the implant transmits detailed electrical signals representing neuronal spikes and broader synaptic patterns.
In tests, researchers implanted the MOTE into the barrel cortex of mice, where it recorded brain activity continuously for 365 days without harming the animals. The success demonstrates that stable, long-term brain monitoring can now be achieved without tethered wires or bulky hardware.
Clinical Potential and Future Applications
This innovation could redefine how brain activity is studied and monitored in both research and medicine. Its minute size and material properties may allow future use of the neural implant during MRI scans, overcoming one of the biggest limitations of current devices. Beyond neuroscience, similar designs could be adapted for the spinal cord or paired with artificial skull plates. For clinicians, such technology may one day support safer and more effective brain–machine interfaces, enhancing diagnosis and treatment of neurological disorders.
Reference
Lee S et al. A subnanolitre tetherless optoelectronic microsystem for chronic neural recording in awake mice. Nat Electron. 2025;DOI:10.1038/s41928-025-01484-1.
