E4UnityIntegration-MIT: An Open-Source Unity Plug-in for Collecting Physiological Data Using Empatica E4 during Gameplay

Physiological measurement of player experience (PX) during gameplay has been of increasing interest within game research circles. A commonly-used non-invasive wearable device for physiological measurement is the Empatica E4 wristband, which ofers multiple physiological metrics, ranging from electrodermal activity to heart rate. That said, the E4's integration with popular game engines such as Unity 3D presents certain challenges due to non-obvious critical bugs in the library and limited documentation applicability within the Unity context. In this paper, we present an open-source Unity plug-in designed to mitigate the challenges associated with integrating the E4 into Unity projects: E4UnityIntegration-MIT. The plug-in exposes the E4's API for interfacing with Unity C# scripts, thereby enabling realtime data collection and monitoring. E4UnityIntegration-MIT also provides the afordance of saving the E4 data into an external fle for data analysis purposes.