Using eye-tracking technology, scientists are discovering clues to how we think and learn
By Annie Murphy Paul
As you read these words, try paying attention to something you usually never notice: the movements of your eyes. While you scan these lines of text, or glance at that ad over there or look up from the screen at the room beyond, your eyes are making tiny movements, called saccades, and brief pauses, called fixations. Scientists are discovering that eye movement patterns — where we look, and for how long — reveals important information about how we read, how we learn and even what kind of people we are.
Researchers are able to identify these patterns thanks to the development of eye-tracking technology: video cameras that record every minuscule movement of the eyes. Such equipment, originally developed to study the changes in vision experienced by astronauts in zero-gravity conditions, allows scientists to capture and analyze that always-elusive entity, attention. The way we move our eyes, it turns out, is a reliable indicator of what seizes our interest and of what distracts us. Scientists are now using eye-tracking technology to explore how we learn from text and images, including those viewed onscreen.
In a study published last year in the Journal of Experimental Psychology, for example, Finnish researchers examined how the type and placement of advertisements affects online reading. Not surprisingly, data from their eye-tracking equipment showed that the sudden appearance of an ad or motion within an ad (think of all those advertisements with frenetically dancing figures,) distracted readers in a way that interfered with their comprehension of the text. But study author Jaana Simola, a cognitive scientist, and her colleagues were able to refine these observations further: ads placed low and to the right of the text were more distracting than those located above the text, and multiple ads containing both animated and static elements were harder to ignore than groups of ads that were either all still or all moving.
Of course, disrupting our attention is what advertising is all about. Scientists are also using eye-tracking technology to discover how to eliminate distraction and improve focus. In a study published in the journal Psychological Science, researchers Elizabeth Grant and Michael Spivey tracked the eye movements of experimental subjects as they viewed a diagram and tried to solve a hypothetical problem: If you were a doctor, how would you use a laser to destroy this patient’s stomach tumor without harming the healthy tissue around it? People who successfully solved the problem, Grant and Spivey found, looked more often at a certain part of the diagram. In round two of their experiment, they visually highlighted this feature — and doubled the number of participants who got the problem right. Showing people’s eyes where to go can actually promote insight and improve reasoning, the authors concluded; in their words, “guiding attention guides thought.”
The ability to focus on the relevant features of a visual scene is one of the most important differences between experts and novices in any field — an ability that is developed over years of looking at countless similar scenarios. But what if the characteristic eye movements of experts could be recorded and then replayed for beginners, giving them a model for how and where to look? That’s what scientists at the University of Exeter in Britain did in a study published last year. The eye movements of an experienced surgeon were captured by eye-tracking equipment and then mapped onto a video of a simulated surgical task, showing where the expert’s gaze would be directed as he performed the operation. Trainee surgeons who watched the video learned much more quickly than students who were taught in more traditional ways, like showing them how to move the surgical instruments with their hands.
Eye movements are so closely tied to the way we think and act that they can even reveal information about our personalities. In a study published this month in the journal Cognition, researcher Aaron Risko and his coauthors asked experimental subjects to complete a questionnaire gauging their levels of curiosity, defined as a desire for new knowledge and new experiences. The scientists then used eye-tracking equipment to record the eye movements of participants as they viewed a series of scenes. People who tested as highly curious, Risko reported, looked at many more elements of the pictures, restlessly moving their eyes around the scenes. “Who a person is,” he concluded, “relates to how they move their eyes.”