5ヶ月齢の単一言語およびバイリンガル乳児における顔面走査パターンの差異なし

It has been suggested that bilinguals take greater advantage of visual speech cues than monolinguals. Therefore, in a sample of 474 (47.3% females) monolingual and 101 (48.5% females) bilingual infants at 5 months of age, we examined the tendency to look at the eyes versus the mouth of dynamic faces, as well as the latency and ratio of looking at a static face interspersed with non-social objects. No significant differences were found for these measures, suggesting that monolingual and bilingual infants orient to and scan faces in a similar way. Although no association was found between the tendency to look at eyes versus mouth at 5 months and vocabulary at 24 and 36 months, a higher tendency to look at the eyes was related to a larger receptive vocabulary at 14 months, but only in the monolingual group (β = 0.15, 95% CI: 0.04; 0.27, p = 0.011). However, the difference in beta values of this association between mono- and bilinguals was not statistically significant. In conclusion, we did not find support for the hypothesis that bilingual infants rely on visual speech cues from the mouth more than monolinguals do, and there was no association between the tendency to look at eyes versus mouth and later language development in the bilingual group. SUMMARY: It has been suggested that bilinguals take greater advantage of visual speech cues than monolinguals. Here, no differences between bilingual and monolingual 5-month-olds were found regarding any measures of face scanning. The findings suggest similar visual attention patterns in mono- and bilingual infants, with no impact on bilingual language development.