Eye-tracking

Eye-tracking technology monitors peoples’ eyes when they look at a screen showing images and/or words. We can see where they look and how much time they spend looking. Looking times tell us something about processing effort. More looking means the brain expended more effort to process what is being fixated by the eye.

For example, we can see if people spend more time reading words in Oliver Twist that differ across different editions. The 1846 Bradbury edition refers to Fagin as the Jew, while the 1867 Chapman & Hall version refers to him as Fagin. Here we see where one participant’s eyes fixated in the two versions (blue circles) and for how long (in milliseconds).

In another example, we can see where people’s eyes go in Google searchers. Which entries do they look at and process longer? 

Heat map of a single person’s looks, with red indicating the most looks. The person spent most of the time looking at the 1st result, but then continued down the page until the 5th one, which was the searched for company’s webpage.