Interactions of culture and depression in infant-directed speech

Abstract

Infant-directed speech (IDS) is a change in voice register adopted by adults when speaking to young children. Maternal depression is known to affect IDS, resulting in a lower fundamental frequency (f0) range that can in turn affect infant response. However, there is little information regarding the interaction of culture and language with depression. The goal of this study was to determine if significant differences in IDS exist between Spanish- and English-speaking mothers and to explore potential interactions with the severity of depression. Whole-day audio recordings were collected in the home from 14 mother-infant dyads, 7 English-speaking and 7 Spanish-speaking, all with infants 6 months of age. 10 examples of adult-directed speech and infant-directed speech were segmented from each recording andthe f0 mean and range were measured for each speaker, normalizing infant-directed by adult-directed values to account for speaker variation. The Edinburgh Postnatal Depression Scale (EPDS) was used to determine maternal depression levels. A weak negative correlation was found between depression scores and f0, confirming that depression adversely impacts IDS, but there was no effect or interaction regarding language, suggesting that the mechanism may be common across cultures.