Virtual Reality (VR) is seeing increased adoption across many fields. The field of experimental cognitive science is also testing utilization of the technology combined with physiological measures such as electroencephalography (EEG) and eye tracking. Quantitative measures of human behavior and cognition process, however, are sensitive to minuscule time resolutions that are often overlooked in the scope of consumer-level VR hardware and software stacks. In this preliminary study, we implement VR testing environments in two prominent 3D Virtual Reality frameworks (Unity and Unreal Engine) to measure latency values for stimulus onset execution code to Head-Mount Display (HMD) pixel change, as well as the latency between human behavioral response input to its registration in the engine environment under a typical cognitive experiment hardware setup. We find that whereas the specifics of the latency may further be influenced by different hardware and software setups, the variations in consumer hardware is apparent regardless and report detailed statistics on these latencies. Such consideration should be taken into account when designing VR-based cognitive experiments that measure human behavior.

翻译：虚拟现实（VR）正被越来越多地应用于多个领域。实验认知科学领域也在测试将这一技术与脑电图（EEG）和眼动追踪等生理测量方法结合使用的可能性。然而，对人类行为与认知过程的定量测量对微小的时序分辨率非常敏感，这在消费级VR硬件和软件堆栈的范畴内往往被忽视。在这项初步研究中，我们在两个主流的3D虚拟现实框架（Unity和Unreal Engine）中实现了VR测试环境，以测量在典型认知实验硬件设置下，从刺激呈现执行代码到头戴式显示器（HMD）像素变化之间的延迟值，以及从人类行为反应输入到其在引擎环境中注册之间的延迟值。我们发现，尽管延迟的具体数值可能进一步受到不同硬件和软件设置的影响，但消费级硬件间的差异仍然明显，并报告了关于这些延迟的详细统计数据。在设计基于VR的测量人类行为的认知实验时，这些因素应当被纳入考量。