Explore a comprehensive guest presentation by Saad Khan on enabling natural human interaction in immersive virtual environments. Delve into applications for doctors, therapists, police, and military personnel. Examine metrics, modalities, and body language variations used in virtual reality. Learn about occupancy, depth training, confusion matrices, and the use of Kinect technology. Discover techniques for recognizing open palm approaches, facial expressions, and paralinguistic features. Investigate feature extraction methods, hidden states, and fusion techniques like early fusion, late fusion, and joint hidden CRF. Conclude with insights on checkpoint scenarios and future directions in this 57-minute talk from the University of Central Florida.