Infant‐Directed Speech Facilitates Word Segmentation

TLDR

Infant‑directed speech is thought to ease language acquisition, yet its effects on learning remain poorly understood, and preference direction in listening paradigms is also examined. The study tests whether infant‑directed speech aids infants in segmenting words from fluent speech. Infants listened to nonsense sentences spoken with either adult‑directed or infant‑directed intonation, using only statistical cues to identify word boundaries. Infants could segment words after hearing infant‑directed speech but not after adult‑directed speech, indicating that infant‑directed speech facilitates word segmentation and may aid broader language acquisition.

Abstract

Abstract There are reasons to believe that infant‐directed (ID) speech may make language acquisition easier for infants. However, the effects of ID speech on infants' learning remain poorly understood. The experiments reported here assess whether ID speech facilitates word segmentation from fluent speech. One group of infants heard a set of nonsense sentences spoken with intonation contours characteristic of adult‐directed (AD) speech, and the other group heard the same sentences spoken with intonation contours characteristic of ID speech. In both cases, the only cue to word boundaries was the statistical structure of the speech. Infants were able to distinguish words from syllable sequences spanning word boundaries after exposure to ID speech but not after hearing AD speech. These results suggest that ID speech facilitates word segmentation and may be useful for other aspects of language acquisition as well. Issues of direction of preference in preferential listening paradigms are also considered.