Asger Risom
A new brain implant developed at Cornell University could transform how scientists monitor neural activity.
A new brain implant developed at Cornell University could transform how scientists monitor neural activity. Barely larger than a grain of salt, the device records and transmits brain signals without wires or bulky equipment — a major step toward safer, longer-lasting neural interfaces.
The world’s smallest brain implant
The microscale optoelectronic tetherless electrode, or MOTE, is only 300 microns long and 70 microns wide — roughly the width of a human hair. Despite its size, it can measure brain activity and send the data out through tissue and bone using infrared light.
“As far as we know, this is the smallest neural implant that will measure electrical activity in the brain and then report it out wirelessly,” said Alyosha Molnar, an electrical engineer and co-author of the study, published in Nature Electronics.
MOTE operates using an aluminum gallium arsenide diode that both harvests energy and transmits data. The system uses optical pulse position modulation — similar to satellite communications — allowing it to send information efficiently while consuming very little power.
Tested in mice for over a year
After successful lab tests, researchers implanted MOTE in the barrel cortex of mice, the brain region responsible for processing whisker sensations. For more than a year, the device consistently recorded neural spikes and wider brain activity, showing long-term reliability.
The team says the design addresses two persistent problems with traditional brain implants: interference during MRI scans and irritation caused by large electrodes or fiber optics. MOTE’s compact, flexible structure minimizes tissue disruption and avoids triggering immune responses.
“Our goal was to make the device small enough to minimize disruption while still capturing brain activity faster than imaging systems,” Molnar said.
Beyond the brain
The implications of the technology extend far beyond neuroscience. Researchers believe the same design could monitor activity in other sensitive tissues, including the spinal cord, or even integrate into artificial skull plates for long-term use.
“Our technology provides the basis for accessing a wide variety of physiological signals with small and untethered instrumentation implanted on chronic timescales,” the study concluded.
Sources: Nature Electronics, Cornell University, Popular Science
This article is made and published by Asger Risom, who may have used AI in the preparation
