title: NEDE: an open-source scripting suite for developing experiments in 3D virtual environments.
abstract: BACKGROUND
  As neuroscientists endeavor to understand the brain's response to ecologically valid scenarios, many are leaving behind hyper-controlled paradigms in favor of more realistic ones. This movement has made the use of 3D rendering software an increasingly compelling option. However, mastering such software and scripting rigorous experiments requires a daunting amount of time and effort.
  
  
  METHODS
  To reduce these startup costs and make virtual environment studies more accessible to researchers, we demonstrate a naturalistic experimental design environment (NEDE) that allows experimenters to present realistic virtual stimuli while still providing tight control over the subject's experience. NEDE is a suite of open-source scripts built on the widely used Unity3D game development software, giving experimenters access to powerful rendering tools while interfacing with eye tracking and EEG, randomizing stimuli, and providing custom task prompts.
  
  
  RESULTS
  Researchers using NEDE can present a dynamic 3D virtual environment in which randomized stimulus objects can be placed, allowing subjects to explore in search of these objects. NEDE interfaces with a research-grade eye tracker in real-time to maintain precise timing records and sync with EEG or other recording modalities.
  
  
  METHODS
  Python offers an alternative for experienced programmers who feel comfortable mastering and integrating the various toolboxes available. NEDE combines many of these capabilities with an easy-to-use interface and, through Unity's extensive user base, a much more substantial body of assets and tutorials.
  
  
  CONCLUSIONS
  Our flexible, open-source experimental design system lowers the barrier to entry for neuroscientists interested in developing experiments in realistic virtual environments.
authors: Department of Biomedical Engineering, Columbia University, New York, NY, USA. Electronic address: djangraw@gmail.com.
authors: David C
authors: DC
authors: Jangraw
authors: Department of Biomedical Engineering, Columbia University, New York, NY, USA.
authors: Ansh
authors: A
authors: Johri
authors: Department of Biomedical Engineering, Columbia University, New York, NY, USA.
authors: Meron
authors: M
authors: Gribetz
authors: Department of Biomedical Engineering, Columbia University, New York, NY, USA; Department of Radiology, Columbia University, New York, NY, USA. Electronic address: psajda@columbia.edu.
authors: Paul
authors: P
authors: Sajda
mesh_terms: D001921:Brain / Q000502:physiology; D002138:Calibration; D004569:Electroencephalography / Q000379:methods; D053483:Eye Movement Measurements; D006801:Humans; D020407:Internet; D012984:Software; D014584:User-Computer Interface; D018910:Video Games
keywords: 3D stimuli; BCI; EEG; Experimental design; Eye tracking; Virtual environment