This fascinating video from the BBC shows how people can see the same thing completely differently. Researchers look at how babies acquire language, and how language acquisition impacts what they see. And then they look at the Himba tribe, which has only five words for color, and can distinguish different hues than typical Westerners. Zhicheng Liu provides a great discussion on linguistic theory and why info viz designers should care.
This research looks at differences between groups of people. One of my favorite artists (Penny Kruse) likes to talk about how no two people see the same scene quite the same. Where each is standing — the perspective, shadows and light — combine to create unique experiences.