Perception of sentence stress in English infant directed speech

Various studies have examined the acoustic features in infant directed speech (IDS) and adult directed speech (ADS). However, there are few speech corpora with prominence annotation from multiple listeners or analysis of the acoustic properties of the stressed versus unstressed words, most studies and corpora focusing on syllabic stress. In order to fill this gap, the current study analyzes the acoustic properties of sentence stress in a corpus of English IDS. More specifically, the work is one of the first analyzing IDS as perceived by adult listeners, providing inter-annotator agreement ratings and an analysis of the acoustic correlates of sentence stress with regard to the most important prosodic features encountered in the literature: fundamental frequency, intensity, word duration, and spectral tilt. The analysis shows that all of the analyzed features correlate with the perception of stress, indicating that the sentential prominence in IDS is conveyed by similar acoustic characteristics that are known to be relevant for stress perception in ADS.