09/15/2026
Doctoral Thesis Defense: Weinan Wang
Date & Time: September 17, 2026, 8:45am
Location: BioScience Research Collaborative 975 (+Zoom)
Host department: ECE / Rice Brain Institute
Advisor: Dr. Chong Xie, Dr. Lan Luan
Committee: Dr. Caleb Kemere, Dr. Nishal Shah, Dr. Christina Tringides
Title: Chronic Large-Scale Neural Recording and Stimulation Enabled by High-Density Ultraflexible Probes, ASIC Integration, and Robotic Implantation
Abstract: Penetrating neural interfaces have transformed neuroscience and neuroengineering by enabling direct access to neuronal activity with single-unit-scale resolution and millisecond temporal precision. Rigid penetrating electrode technologies, from Utah arrays to high-density silicon probes such as Neuropixels, provide large-scale electrophysiological access and mechanically robust insertion, but their stiffness, fixed geometries, and mechanical mismatch with brain tissue can constrain chronic and distributed applications. Meeting the needs of next-generation neural interfaces will require high channel count, chronic tissue integration, distributed access to multiple brain regions, and programmable bidirectional operation. Ultraflexible polymer probes such as NETs (NanoElectronic Threads) better match tissue mechanics and can support stable chronic recordings, but their small dimensions make it difficult to scale electrode density, route independent interconnects, and implant many threads.
This dissertation describes scalable ultraflexible neural-interface technologies that address these limitations through high-density probe fabrication, integrated bidirectional electronics, and robotic implantation. First, we developed electron-beam-lithography-defined ultraflexible polymer probes (EBL-NETs) that increase electrode density while preserving a small implantation footprint and tissue-compliant mechanics. Dense e-beam-patterned interconnects enable independent routing to hundreds of electrodes on a single shank, with designs reaching up to 512 channels per shank. In parallel, we integrated a four-shank, 512-channel probe system with a custom application-specific integrated circuit, enabling large-scale in vivo recording across distributed neural populations. In vivo validation with 128-channel EBL-NETs showed dense single-unit recordings over months in rats, with stable unit waveforms and metrics. Intracortical microstimulation experiments in mice further showed consistent stimulation-evoked activation across animals, demonstrating the potential of this platform for chronic bidirectional neural interfacing.
Second, we developed Centimani, a precision robotic implantation system for minimally invasive, large-scale placement of flexible neural probes. Centimani uses 32 independently addressable arms to implant flexible threads in programmable spatial configurations, supporting simultaneous or sequential insertion, sub-100µm targeting accuracy, inter-thread spacing down to 500µm, and programmable insertion speeds spanning the micrometer-per-second regime up to 10mm/s. By reducing manual handling and enabling parallel, independently controlled implantation, Centimani addresses a major surgical bottleneck for distributed flexible-probe interfaces.
Together, these technologies establish a scalable framework for chronic, high-density, bidirectional neural interfacing with ultraflexible probes. The EBL-NETs–ASIC platform enables dense interrogation of local circuits, while Centimani enables distributed access to long-range interactions across brain regions. This work expands the experimental space for studying local circuit computation, distributed brain dynamics, and closed-loop neural interfaces.
