Called the microscale optoelectronic tetherless electrode (MOTE), the device has already demonstrated its ability to measure sharp neuron spikes and broader brain signals with minimal impact on brain tissue. By using light to power the implant and transmit data, it opens up new possibilities for continuous, chronic neural monitoring, something that has remained elusive with previous technologies.
Advancements in Neural Recording
The MOTE represents a significant step forward in the field of neural monitoring. At just 300 microns long and 70 microns wide, it is small enough to balance on a grain of salt, but powerful enough to wirelessly track neural activity for over a year.
According to researchers, this is the smallest neural implant capable of such long-term, high-resolution recordings. The device uses harmless red and infrared lasers to power the implant, while infrared light pulses encode the brain’s electrical signals and transmit them without the need for physical wires.
This novel approach is critical for understanding complex brain behaviors and disorders, as it eliminates the need for traditional electrodes or optical fibers, which can cause irritation and immune responses in brain tissue. The MOTE’s small size and tetherless design allow it to be minimally invasive, avoiding the mechanical damage typically caused by larger, wired devices.
Long-Term Testing Proves Its Worth
In animal trials, the MOTE has been shown to function effectively over the course of a year. Researchers implanted the device in the brains of mice, specifically in the barrel cortex, which processes sensory information from whiskers. Over 365 days, the implant continuously recorded both sharp neuron spikes and local field potentials (LFPs), offering an unprecedented look at brain activity over extended periods.
Tests on mice confirmed the device’s durability and reliability, with the animals remaining healthy throughout the year-long study. According to Alyosha Molnar, the project’s lead investigator at Cornell University, the goal was to design a system that would avoid irritating brain tissue. Traditional implants can trigger immune responses, but the MOTE’s small size helps minimize that risk.
The team hopes that the MOTE could eventually be used for more than just mice, potentially offering a new tool for studying brain activity in a wide range of animals or even for human applications, such as continuous monitoring during brain scans or post-surgical interventions.
A New Era for Neuroscience and Beyond
The impact of the MOTE goes beyond its revolutionary use in neuroscience. Because the device is powered by light and transmits data optically, it could allow for simultaneous neural monitoring during techniques such as MRI scans, something current implants are unable to do due to interference from electromagnetic fields. This opens up exciting possibilities for non-invasive, real-time tracking of neural activity across various medical settings.
Molnar’s research began in 2001, but it was only in the past decade, through collaborations with Cornell Neurotech, that the team was able to bring the MOTE to fruition. Now, they see potential for adapting the technology for other uses, such as monitoring the spinal cord or even embedding the devices into artificial skull plates for long-term brain monitoring.
By combining electrical and optical technology, the MOTE addresses one of the greatest challenges in brain research: how to capture long-term data without causing harm to the brain or interfering with natural biological processes. According to the study published in Nature Electronics, this new implant could pave the way for ongoing, unobtrusive monitoring of the brain, which is crucial for advancing our understanding of neural functions and disorders.
