An Expandable Brain‐Machine Interface Enabled by Origami Materials and Structures for Tracking Epileptic Traveling Waves

Abstract Tracking neural activities across multiple brain regions remains a daunting challenge due to the non‐negligible skull injuries during implantations of large‐area electrocorticography (ECoG) grids and the limited spatial accessibility of conventional rectilinear depth probes. Here, a multiregion Brain‐machine Interface (BMI) is proposed comprising an expandable bio‐inspired origami ECoG electrode covering cortical areas larger than the cranial window, and an expandable origami depth probe capable of reaching multiple deep brain regions beyond a single implantation axis. Using the proposed BMI, it is observed that, in rat models of focal seizures, cortical multiband epileptiform activities mainly manifest as expanding traveling waves outward from a cortical source.