Examining infants' preferences for tempo in lullabies and playsongs.

Caregivers around the world sing to their infants. Infants not only prefer to listen to infant-directed singing over adult-directed singing, but infant-directed singing also serves a function, communicating affective information to preverbal infants to aid in adjusting arousal levels. Pitch variation has previously been identified as one performance feature that may help to convey the message. Earlier research has indicated that infants' pitch preferences are context dependent, suggesting that infants are tuned in to the communicative intent of infant-directed singing. However, there are several other performance-based features present in infant-directed singing that may also contribute to the affective message. The current study examined the role of context on infants' tempo preferences in sung playsongs and lullabies. Using a head-turn preference procedure, we measured 24 preverbal infants' natural preferences for foreign language playsongs and lullabies as a function of tempo. Infants showed a preference for fast over slow tempo playsongs, but no such context dependent preference was found within lullabies. Results partially support the role of tempo as a communicative feature of infant directed singing.

Does the message matter? The effect of song type on infants' pitch preferences for lullabies and playsongs.

Preverbal infants are attuned to the different emotional messages contained in playsongs and lullabies. However, it is unclear which performance properties of singing underlie infants' perception of the communicative intent of infant-directed singing. Volkova, Trehub, and Schellenberg (2006) recently demonstrated that 6- and 7-month-old infants preferred low-pitched to high-pitched renditions of lullabies, suggesting that pitch may be one performance characteristic that conveys the communicative intent in infant-directed singing. In the current study, we evaluated 6- and 7-month-old infants' natural preferences for unfamiliar, expressive lullabies and playsongs as a function of pitch using a head-turn preference procedure. Infants preferred low-pitched over high-pitched versions of lullabies and high-pitched over low-pitched versions of playsongs. Results suggest that the overall pitch of a song is communicative to infants and that the affective nature of music can have an effect on infants' pitch preferences. That is, infants' preferences for pitch are context-dependent.