The influence of infant-directed speech on 12-month-olds' intersensory perception of fluent speech

TL;DR

This study investigates how infant-directed speech influences 12-month-olds' ability to match audio-visual speech cues, revealing that ID speech enhances native language perception but not non-native language matching.

Contribution

It demonstrates that infant-directed speech facilitates intersensory matching of fluent speech in infants, highlighting its role in early multisensory perceptual development.

Findings

Infants did not match audio-visual speech in adult-directed condition.

ID speech improved native language matching in infants.

Non-native language matching was not facilitated by ID speech.

Abstract

The present study examined whether infant-directed (ID) speech facilitates intersensory matching of audio--visual fluent speech in 12-month-old infants. German-learning infants\^a audio--visual matching ability of German and French fluent speech was assessed by using a variant of the intermodal matching procedure, with auditory and visual speech information presented sequentially. In Experiment 1, the sentences were spoken in an adult-directed (AD) manner. Results showed that 12-month-old infants did not exhibit a matching performance for the native, nor for the non-native language. However, Experiment 2 revealed that when ID speech stimuli were used, infants did perceive the relation between auditory and visual speech attributes, but only in response to their native language. Thus, the findings suggest that ID speech might have an influence on the intersensory perception of fluent speech and shed further light on multisensory perceptual narrowing.