Cornell University researchers in the U.S. have developed the world’s smallest wireless brain implant—smaller than a grain of rice—ushering in a new era of neurotechnology and precision neuroscience.
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| Cornell researchers in New York have built the smallest brain implant ever—a wireless, infrared-powered device that could revolutionize neuroscience and future brain–computer interfaces. Image: CH |
ITHACA, United States — November 9, 2025:
A team of researchers at Cornell University has developed a brain implant smaller than a grain of rice, marking a groundbreaking step in the evolution of neurotechnology. The device, officially called a microscale optoelectronic tetherless electrode (MOT), can monitor and transmit brain activity data wirelessly using infrared light, allowing for unprecedented precision and minimal invasiveness.
“This is the smallest neural implant ever made,” said Alyosha Molnar, the project’s lead scientist. Measuring only 300 micrometers long and 70 micrometers wide—roughly the width of a human hair—the MOT can read electrical activity in the brain and transmit information without the need for external wires or bulky receivers.
The implant’s optical system converts neural signals into coded light pulses that pass through brain tissue and bone to reach a receiver. Built from aluminum gallium arsenide, the device is capable of simultaneously harvesting energy and transmitting data—an engineering achievement inspired by the principles of modern microchips. It uses pulse position modulation to ensure efficient, low-power communication.
Molnar first envisioned the concept in 2001, but after nearly two decades of development, the technology has finally reached a viable prototype stage. In laboratory experiments, the MOT was successfully implanted in the barrel cortex of rats, where it recorded neural activity for over a year without causing inflammation or immune responses—an improvement over conventional electrodes that often irritate brain tissue.
“Our goal was to design an implant so small and efficient that it could capture brain signals without disrupting normal function,” Molnar explained. “We see potential not just in brain research, but also in other delicate areas like the spinal cord.”
If proven safe in humans, this innovation could redefine how scientists monitor and interact with the nervous system. From treating neurological disorders to advancing brain–computer interfaces, the MOT offers a glimpse into a future where brain data can be captured with minimal interference.
Cornell’s achievement represents a critical leap in neuroengineering, bridging the gap between biological systems and digital technology—and pushing the boundaries of what’s possible in human–machine integration.