An eye-tracking study of letter-sound correspondence in Japanese-speaking 2- to 3-year-old toddlers.

Although the acquisition of letter-sound correspondences is a critical step in reading development, how and when children develop such correspondence remains relatively unexplored. In this study, we focused on Japanese hiragana letters to examine the implicit letter-sound correspondence using an eye-tracking technique for 80 Japanese-speaking toddlers. The results showed that 32- to 48-month-olds (but not 24- to 32-month-olds) directed their gaze at the target letter. An additional experiment on a letter-reading task showed that 32- to 40-month-olds could barely read the presented hiragana letters. These findings suggest that toddlers have already begun to grasp implicit letter-sound correspondences well before actually acquiring the ability to read letters.