Abstract
As soon as an observer opens their eyes, they have the immediate impression of a rich, colorful experience that encompasses their entire visual world. Here, we show that this impression is false. We used gaze-contingent rendering in immersive virtual reality (VR) to reveal the limits of color awareness during real-world visual experience. We exploited recent developments in head-mounted VR to immerse observers (N=160) in dynamic, audio-visual, real-world environments (e.g., a symphony rehearsal, etc.). Observers naturally explored these environments in whatever way they chose via saccades and head turns. Meanwhile, we monitored their gaze with in-headset eye tracking. Then, with observers having no expectation that anything different was about to occur, we altered the visual environments such that only the parts of the scene they were looking directly at were presented in color. The rest of the scene in the periphery was entirely desaturated. Overall, we found that observers routinely failed to notice when color completely vanished from the overwhelming majority of their visual world. In the most extreme case, almost a third of observers failed to notice when less than 3% of the visual world was presented in color, while everything else was desaturated. However, when those observers were shown the same displays a second time and instructed to attend to their periphery, every observer immediately detected the altered periphery and was astonished that they did not previously notice. In a second study (N=20), we measured color detection thresholds using a staircase procedure while observers attended to the periphery. Once again, we found that observers were unaware when a large portion of their field of view was presented in greyscale. Together, these results provide the first measurements of color awareness during active, naturalistic viewing conditions, and show that our intuitive sense of a rich, colorful visual world is largely incorrect.