A team of researchers led by neurotechnology expert Stephanie Lacour from Switzerland’s Ecole Polytechnique Fédérale de Lausanne has made significant progress in the development of a less invasive method for treating brain conditions that require implantation. Inspired by soft robots, the researchers have created a groundbreaking cortical electrode array capable of passing through a small opening in the skull.

Cortical electrode arrays are used to stimulate, record, or monitor electrical activity in the brain of patients suffering from conditions like epilepsy, which affects approximately 1.2 percent of the US population. Epilepsy often results in seizures, characterized by bursts of electrical activity in the brain, leading to uncontrollable shaking, sudden stiffness, collapsing, and other symptoms. Although microelectrode arrays were invented several decades ago, their use in deep brain stimulation for epilepsy patients has only recently received FDA approval. Nonetheless, existing devices have limitations in terms of electrode resolution, cortical surface coverage, and aesthetic appeal, as noted by the authors of the research paper.

The team has developed an ultra-thin, flower-shaped device that can be folded to fit through a 2 centimeter hole in the skull. Once inside, it rests between the skull and the brain’s surface, occupying a minute and delicate space measuring approximately a millimeter in width. Upon deployment, the flexible electrode unfurls its six spiraled arms one by one, covering an area of the brain around 4 centimeters in diameter. In contrast, other devices often require a skull opening of the same diameter as the electrode array.

Lead author Sukho Song commented on the mechanism, stating, “The beauty of the eversion mechanism is that we can deploy an arbitrary size of electrode with a constant and minimal compression on the brain. The soft robotics community has been very much interested in this eversion mechanism because it has been bio-inspired. This eversion mechanism can emulate the growth of tree roots, and there are no limitations in terms of how much tree roots can grow.”

Although the device has only been tested in a mini-pig and is not yet ready for use in human brains, it will be further developed by Neurosoft Bioelectronics, a spinoff of the EPFL Laboratory for Soft Bioelectronic Interfaces. Stephanie Lacour emphasized the importance of minimally invasive neurotechnologies in providing efficient and personalized therapies, stating, “Minimally invasive neurotechnologies are essential approaches to offer efficient, patient-tailored therapies.”

By Impact Lab