Using data generated by cameras trained on readers' eyes, the research team has found that patterns of eye movement -- particularly how long people's eyes rest on certain words -- correlate strongly with performance on standardized tests of English as a second language.

"To a large extent [eye movement] captures linguistic proficiency, as we can measure it against benchmarks of standardized tests," says Yevgeni Berzak, a postdoc in MIT's Department of Brain and Cognitive Sciences (BCS) and co-author of a new paper outlining the research.

He adds: "The signal of eye movement during reading is very rich and very informative."

The paper, "Assessing Language Proficiency from Eye Movements in Reading," is being published in the Proceedings of the 16th Annual Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies.

The authors are Berzak, a postdoc in the Computational Psycholinguistics Group in BCS; Boris Katz, a principal research scientist and head of the InfoLab Group at MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL); and Levy, who also directs the Computational Psycholinguistics Lab in BCS.

The study delves into a phenomenon about reading that we may never notice, no matter how much we read: Our eyes do not move continuously along a string of text, but instead fix on particular words for up to 200 to 250 milliseconds.

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