Infants' Preference for the Predominant Stress Patterns of English Words

TLDR

Language acquisition requires infants to segment utterances into words, and in English most words have a strong initial syllable. The study investigates whether infants use sensitivity to predominant stress patterns to aid lexical development. The authors tested infants' listening preferences for strong/weak versus weak/strong stress patterns across three experiments. Nine‑month‑old infants preferentially listened to strong/weak stress patterns, a preference absent at six months and persisting even with low‑pass filtered input, indicating that sensitivity to predominant stress patterns supports lexical development.

Abstract

One critical aspect of language acquisition is the development of a lexicon that associates sounds and meanings; but developing a lexicon first requires that the infant segment utterances into individual words. How might the infant begin this process? The present study was designed to examine the potential role that sensitivity to predominant stress patterns of words might play in lexical development. In English, by far the majority of words have stressed (strong) initial syllables. Experiment 1 of our study demonstrated that by 9 months of age American infants listen significantly longer to words with strong/weak stress patterns than to words with weak/strong stress patterns. However, Experiment 2 showed that no significant preferences for the predominant stress pattern appear with 6-month-old infants, which suggests that the preference develops as a result of increasing familiarity with the prosodic features of the native language. In a third experiment, 9-month-olds showed a preference for strong/weak patterns even when the speech input was low-pass filtered, which suggests that their preference is specifically for the prosodic structure of the words. Together the results suggest that attention to predominant stress patterns in the native language may form an important part of the infant's process of developing a lexicon.