1. An image generation system for generating an image on a display screen, the image generation system including: an eye-tracking system capable of determining a user's eye orientation and outputting a signal indicative of same; a bio-feedback sensor capable of detecting activity of one or more physiological functions of the user and outputting a signal indicative of the level of activity; and a processor adapted to receive and process the output signals from the eye-tracking system and bio-feedback sensor; wherein the processor determines an image to be generated on the display screen indicative of the signals from the eye-tracking system and bio-feedback sensor.