Immersive virtual reality environments could be successfully used in different research and development areas such as architecture, manufacturing, art and design, human-computer interaction, visual analytics, molecular dynamics, safety applications including crowd simulation, etc. In this paper, we proposed and implemented integration of EEG-based interaction and immersive virtual reality system allowing the user’s seamlessness interaction with 3D virtual environments in the Immersive Room (IR). Portable EEG reading devices could be used to input the user’s current brain state including emotions, concentration level, etc. Two applications were proposed and implemented in the Immersive Room system. In the first application, the user’s emotions recognized from EEG were visualized as the dancing movements of penguin avatars in the 3D environment representing the snow city implemented with the IR EON software. In another application, the implemented 3D environment could be changed by the user voluntarily when he/she was trying to concentrate in opposite to relax. Here, the user’s concentration effort could bring the change to the 3D environment: disaster such as tsunami could happen in the implemented virtual city.