Implicit letter-sound knowledge in Japanese-speaking children

Implicit letter-sound knowledge in Japanese-speaking children

First Author: Hiroki Higuchi -- NTT Communication Science Laboratories
Additional authors/chairs: 
Yuko Okumura; Tessei Kobayashi
Keywords: letter-sound integration, Eye-tracking, implicit knowledge, Japanese
Abstract / Summary: 

Purpose: Although letter-sound knowledge acquisition is a critical step for reading development, how such knowledge emerges remains largely unknown. Given previous evidence in vocabulary development where 14-month-olds mapped a word onto an object before producing common nouns (e.g., Werker et al., 1998), children may acquire an implicit ability to map a sound onto a letter (i.e., emergent letter-sound knowledge) before beginning to name letters. Our study used an eye-tracking technique and focused on Japanese hiragana letters to investigate whether children possess emergent letter-sound knowledge.

Method: Based on previous evidence that Japanese-speaking children begin to learn hiragana after three years of age (Shimamura & Mikami, 1994), we measured the eye movements of 2- to 3-year-old children (N=80). As two hiragana letters were presented side by side on the screen, a target hiragana letter was auditorily presented. Emergent letter-sound knowledge was indexed based on the ‘increase in target looking’: the looking ratio at target letter (ex. ‘み’) minus its ratio (‘み’) when this letter was presented as a distracter (Bergelson & Swingley, 2013).

Results: In the young-age group (N=22, M=28.2 mo, range: 24.8-31.9 mo), the children did not show a significantly larger value from zero (p=0.85, Wilcoxon test). In contrast, the middle- (N=41, M=35.9 mo, range: 32.0-40.0) and old-age groups (N=17, M=46.1 mo, range: 44.7-48.0) showed no significantly larger values from zero (p=0.03 and p<.001). After the eye-tracking experiment, we checked their letter-sound-naming performance. Although the children in the young- and middle-age groups could barely read the presented hiragana letters (M=0.0±0.2 letters; M=1.0±3.6 letters), those in the old-age group could slightly read them (M=1.2±3.7 letters).

Conclusion: Our present result implies that children have already acquired emergent letter-sound knowledge well before they can name letter sounds.