Foldable three dimensional neural electrode arrays for simultaneous brain interfacing of cortical surface and intracortical multilayers

Challenges in understanding three-dimensional brain networks via simultaneous recordings from cortical surface and intracortical areas persist due to mechanical design constraints and spatial limitations at implant sites. Here, we present a foldable, flexible 3D neural prosthetic that enables mapping of complex neural circuits with high spatiotemporal dynamics from intracortical to cortical regions. The device integrates four flexible penetrating shanks and surface electrode arrays in one system to map 3D neural transmission. We demonstrate identification of correlations between intracortical and cortical activities through continuous electrophysiological monitoring. Leveraging the device’s structural properties, we recorded synchronized single spikes evoked by unidirectional total whisker stimulation. This platform offers opportunities to clarify unpredictable 3D neural pathways and provides a next-generation neural interface.