Acoustic parameters of infant-directed singing in mothers with depressive symptoms.

The purpose of this study was to explore the relationship between mothers' depressive symptoms and the acoustic parameters of infant-directed (ID) singing. Participants included 80 mothers and their 3- to 9-month-old infants. A digital recording was made of each mother's voice while singing to her infant. Extraction and analyses of vocal data revealed a main effect of tempo, meaning that as mothers reported more depressive symptoms, they tended to sing faster to their infants. Additionally, an interaction effect indicated that mothers with depressive symptoms were more likely to sing with tonal key clarity to their male infants. These findings suggest that as mothers experience depressive symptoms, their ID singing may lack the sensitivity and emotional expression that infants need for affect regulation. An intervention that combines interaction coaching and ID singing may help mothers with depressive symptoms to engage in sensitive and emotionally synchronized interactions with their infants.