Researchers in Denmark and the United Kingdom have built a flexible brain implant less than half a millimeter across that can record electrical signals, stimulate neurons with light, and deliver fluids at multiple depths through a single fiber. In tests in living mice, the device worked in both shallow and deep brain regions, according to a study published in Advanced Science and announced by the Technical University of Denmark on Sept. 21.
The device, called the microfluidic Axialtrode, or mAxialtrode, is a research tool. It has not been tested in people, and its developers say it is still far from clinical use.
About 3.4 million Americans had active epilepsy in 2015, according to federal estimates. For them and their families, the study offers a glimpse of how scientists may study seizures in the future. It is not a new treatment option.
One Fiber, Three Jobs
The implant was developed by researchers at the Technical University of Denmark, the University of Copenhagen, University College London, and other institutions, according to the DTU announcement. It starts as a larger polymer rod that is heated and drawn into a thin, flexible fiber.
A light-carrying core runs through the center, surrounded by eight microscopic channels that can carry liquids or hold ultrathin metal wires to record brain activity. An angled tip lets the fiber interact with tissue at several points along its length, rather than only at the end like conventional optical fibers.
In mice, the team stimulated neurons with blue and red light while recording activity from the cerebral cortex and the deeper hippocampus. They also injected substances at separate depths spaced almost three millimeters apart. The mice carried the lightweight fiber without obvious signs of discomfort.
Softer Materials Aim to Reduce Brain Irritation
"Most current brain implants are based on hard materials such as silicon, which can irritate the brain and trigger inflammatory reactions in the tissue," said Kunyang Sui, a postdoctoral researcher who developed the concept with Associate Professor Christos Markos. The new implant uses soft, plastic-like optical fibers designed to move with brain tissue.
Sui cautioned that extensive testing, further development, and regulatory approvals would be needed before the device could be used to treat patients. The team is working to patent the technology and exploring what clinical testing would require.
Limits of an Early Animal Study
This study tested whether the device works, not whether it treats any disease. It was an engineering and proof-of-concept study, so it did not measure seizures, memory, or behavior in a way that would show a health benefit. Mouse brains are far smaller and simpler than human brains, and results in animals often do not carry over to people. The announcement did not describe long-term safety over months or years, which matters for any implant meant to stay in the brain.
The researchers say the tool could help scientists study how signals travel across brain layers in epilepsy, memory, and decision-making. Over the longer term, they say, it could deliver drugs to precise spots while stimulating nearby areas. That remains a hypothesis. The full paper describes the device's engineering and mouse experiments.
Epilepsy Patients Already Have Proven Options
Epilepsy affected about 1.2% of the U.S. population, or 3.4 million people, in 2015, according to a CDC report. Many people control seizures with medication. For those who do not, specialists can evaluate options such as surgery, dietary therapy, and FDA-approved neurostimulation devices.
People with frequent or uncontrolled seizures can ask for a referral to a comprehensive epilepsy center, where teams can review medication history, imaging, and brain wave testing. Families can also ask about seizure action plans for school and work, which remain one of the most practical safety tools available. Anyone interested in research can search ClinicalTrials.gov and review any study with their neurologist before enrolling.
Seek emergency care for a seizure lasting more than five minutes, repeated seizures without recovery between them, a seizure with injury or trouble breathing, or a first-ever seizure.
Brain implant research is moving quickly. MedicalDaily recently reported on a wireless brain implant that helped a Michigan woman with motor neuron disease communicate in real time. The mAxialtrode is at a much earlier stage: a lab tool that may help scientists ask better questions about the brain.
Key Questions Answered
What is the mAxialtrode? A flexible, needle-thin brain implant that records electrical activity, stimulates neurons with light, and delivers fluids through one fiber.
Has it been tested in people? No. It was tested only in living mice.
Could it treat epilepsy? Researchers say it might eventually, but that is unproven. For now, it is a research tool for studying brain circuits.
Why use a soft implant? Implants made of hard materials such as silicon can irritate brain tissue. Softer fibers are designed to move with the brain.
What options exist now for hard-to-control epilepsy? Specialists can evaluate surgery, dietary therapy, and FDA-approved neurostimulation devices.
When is a seizure an emergency? A seizure lasting more than five minutes, repeated seizures, injury, trouble breathing, or a first seizure needs emergency care.
Published by Medicaldaily.com
