A MEDIAted Extended Reality Experience for the Biometric Assessment of Fear Responses. The use of extended realities such as virtual reality (VR) and immersive media in scientific research is growing rapidly, offering unique and powerful capabilities that can enhance research in many disciplines, including psychology, neuroscience, medicine, and engineering. VR can be used to create simulated environments that allow researchers to study human behavior and brain function in ways that would be difficult or impossible in the real world. As practitioners operating at the intersection of art and technology, it is vital to demonstrate how emerging computational media can contribute to the advancement of scientific research. To this end, we propose a collaboration with the Champalimaud Research Center in Lisbon, Portugal, to design and develop extended reality experiences that will instigate fear and introduce the variable of freezing as a defensive behavior as part of the experience. These studies aim to assess biometric responses, including cardiac activity and eye movement patterns in humans, when responding to fear through freeze as a defensive behavior. Recently, fruit fly research identified cardiac activity as a potential predictor of freezing, and the researchers now seek to validate these findings in humans. Furthermore, there is a link between subtle deviations in freezing behavior and the risk for threat-related maladaptive behavior, including the development of post-traumatic stress disorder (PTSD) in humans. Using XR experiences in scientific trials will allow us to contribute to the current literature on VR experiences in fear assessment, which mainly focuses on patterns of fight and flight and not on freezing behaviors. In summary, this proposal aims to explore the use of XR experiences in scientific research trials to better understand the human response to fear and freezing behavior, which could have implications for a range of disciplines, including psychology, medicine, and neuroscience.