8. People can Miss Changes in their Visual Fields

Slide 1

• Gorilla Video (video/mp4)
• Legenda: https://youtu.be/vJG698U2Mvo
• The “Gorilla video” is an example of inattention blindness or change blindness. The idea is that people often miss large changes in their visual fields.
• Christopher Chabris and Daniel Simons (2010) describe in the book "The Invisible Gorilla" additional research they did with eye-tracking equipment. Eye tracking is a technology that can track where someone is looking. It tracks where the foveal or central gaze is. It doesn’t track peripheral vision. Eye-tracking research done while people are watching the basketball/gorilla video shows that everyone watching the video “sees” the gorilla in the video, meaning that their eyes are looking at the gorilla, but only 50 percent are aware that they have seen the gorilla.
• If you are paying attention to one thing, and you don’t expect changes to appear, then you can easily miss changes that do occur.

Slide 2

• Eye tracking is a technology that allows you to see and record what a person is looking at, in what order, and for how long. It is often used to study Web sites to see where people are looking, including where they look first, second, and so on. But eye-tracking data can be misleading for several reasons:
• Eye tracking tells you what people looked at, but that doesn’t mean that they paid attention to it.
• Peripheral vision is just as important as central vision. Eye tracking measures only central vision.
• What people look at depends on what questions they are asked while they are looking. It’s therefore easy to accidently skew the eye-tracking data depending on what instructions you give them before and during the eye tracking study.
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• Legenda: http://www.eyegaze.com/3-amazing-objectives-eye-tracking-technology-can-achieve/