The BIOPAC virtual reality platform provides controlled and replicable experimental setups and allows manipulation of the environment (and avatars) that would be impossible or prohibitively expensive in the real world. Synchronization of events from the virtual world with physiological data from an MP System allows accurate and automated data analysis. The linking protocol allows you to use a feedback loop for greater control and automation of the VR world; change the VR world in real time, based on the subject's responses.