A neural implant developed at Cornell takes, in the image, a grain of salt.
Innovative tiny, laser-powered implant can read brain activity.
A team of researchers at Cornell University has developed a neural implant so small it can rest on a grain of salt — but can still record electrical activity in the brain and transmit it wirelessly for more than a year.
The remarkable breakthrough, at Nature Electronics in November, introduces us to the MOTE (microscale optoelectronic tetherless electrode or, in Portuguese, microscopic and wireless optoelectronic electrode).
With about 300 micrometers compression and 70 micrometers lengththe implant stands out for combining extremely small dimensions with the ability to operate autonomously within living tissue.
According to the researchers, led by Alyosha Molnar, professor at Cornell’s School of Electrical and Computer Engineering, in collaboration with Sunwoo Lee, currently an assistant professor at Nanyang Technological University in Singapore, MOTE is, as far as they know, the smallest neural implant capable of measuring electrical signals from the brain and communicating them wirelessly to the outsidewhich could pave the way for new, much less invasive forms of brain monitoring and a new generation of miniaturized biomedical sensors.
Unlike many current systems, which rely on invasive cabling, MOTE turn to the light to function. The device is powered by red and infrared laser beams that safely pass through brain tissue. It then transmits the collected data through small pulses of infrared light, encoding the electrical signals detected in the brain.
At the heart of this technology is a semiconductor diode made from aluminum gallium arsenide, responsible both for capturing light to power the system and for emitting light to send information, explains . The implant also integrates a low-noise amplifier and an optical encoder, built with technology similar to that used in conventional microchips.
According to Molnar, one of the potential advantages of MOTE is the possibility of being Compatible with MRI scanssomething that current implants hardly allow.
The team also believes that the technology could be adapted to other regions of the body, including the spinal cord, and could be combined with future biomedical solutions, such as optoelectronic components incorporated into artificial cranial plates.
For scientists, the advance demonstrates that microelectronic systems can continue to shrink without losing functionality and this could transform brain research and the development of future medical devices.
