Printing-assisted integration of thermal, fluidic and electrical components in implants for focal brain cooling

The limitations of electrical neuromodulation are driving the development of neuroprosthetic systems enhanced with complementary modalities. A key technological challenge however remains the integration of the necessary hardware components (optical, thermal, fluidic, electrical) into miniaturized implants. Here we present a design framework, inspired by fast prototyping, that promises to reduce the complexity, fabrication time, and device bulk of multimodal neural interface systems. By combining extrusion-based 3D printing of silicones and discrete electronic components, we integrated thermal neuromodulation and electrical recording capabilities in soft packages suitable for placement on the cortical surface of rodents. When linked to an autonomous auxiliary driver unit, these packages establish rapid, stable and localized hypothermia together with ElectroCorticoGraphy (ECoG) recording. In a rodent model of epilepsy (4-aminopyridine), we demonstrate hypothermia-induced suppression of seizure-like activity. Our approach may advance the clinical translation of focal hypothermia as an alternative therapy for drug-resistant focal epilepsies.