Something like this was the focus of my MFA thesis work, but instead I was trying to make the user be more in focus or in a mindful state in order to trigger scene changes and object animation (it is not a game but a meditative experience). I used Interaxon’s Muse EEG band. There are some issues such as the difficulty of placing the HMD (I used a DK2) over the EEG band without affecting the contact between the electrodes and the skin. Head movement also affects the EEG readings but those can be filtered out using the Muse’s accelerometer (or the HMD’s). The EEG data was easy to get into UE4 using OSC messages and the UE4-OSC plugin https://github.com/monsieurgustav/UE4-OSC. The Muse connects via Bluetooth but there’s a provided command line application that converts the data automatically into OSC messages. There’s also the issue of actually being able to determine the user’s mental state accurately without an individual calibration process, but that’s a general issue of any EEG based project.
