NERV: A Comprehensive Framework for Rapid, Reproducible, and Hardware-Synchronized Neuroscience Experiment Design and Execution.

Background: Behavioral neuroscience experiments require precise stimulus control, millisecond timing, hardware integration, and robust data provenance. Increasing use of 3D environments and multimodal recordings adds challenges for development, accessibility, and reproducibility. Fragmented tools often separate presentation, synchronization, and logging, leading to inefficiencies. New Method: The Neuroscience Experimental Runtime by Vanderbilt (NERV) is a Unity-based framework that unifies experiment design, execution, and data logging. It enables rapid, no-code prototyping by automating scene and script generation, event timing, state management, hardware-synchronized data acquisition, and archival of code and experimental configurations. The modular, open-source framework implements a "low floor, high ceiling" design that lowers barriers for non-programmers while remaining extensible for advanced customization. Results: Across 500 trials, Unity-to-TTL delay was 2.10 ± 1.21 ms, TTL-to-photodiode delay was 28.93 ± 0.76 ms, and Unity-to-screen delay was 31.04 ± 1.41 ms. These results confirm stable millisecond precision and frame-locked timing, enabling reliable alignment of neural, behavioral, and visual events. Comparison with existing methods: Existing frameworks involve trade-offs. Some achieve precise timing but require advanced coding, while others improve accessibility but struggle with hardware or 3D graphics. Commercial platforms offer polish yet remain costly, closed-source, and inflexible. NERV combines millisecond precision, modular open-source design, and provenance in a single platform, reducing workflow fragmentation and enabling reproducible, scalable experiments. Conclusion: NERV is an accessible yet extensible framework that unites rapid development, robust data provenance, and millisecond precision. It accelerates development, ensures reproducibility, and establishes a scalable foundation for next-generation neuroscience research.