Familiar songs reduce infant distress.

Abstract

Parents commonly vocalize to infants to mitigate their distress, especially when holding them is not possible. Here we examined the relative efficacy of parents' speech and singing (familiar and unfamiliar songs) in alleviating the distress of 8-and 10-month-old infants (n = 68 per age group). Parent-infant dyads participated in three trials of the Still Face procedure, featuring a 2-min Play phase, a Still Face phase (parents immobile and unresponsive for 1 min or until infants became visibly distressed), and a 2-min Reunion phase in which caregivers attempted to reverse infant distress by 1) singing a highly familiar song, 2) singing an unfamiliar song, or 3) expressive talking (order counterbalanced across dyads). In the Reunion phase, talking led to increased negative affect in both age groups, in contrast to singing familiar or unfamiliar songs, which increased infant attention to parent and decreased negative affect. The favorable consequences were greatest for familiar songs, which also generated increased smiling. Skin conductance recorded from a subset of infants (n = 36 younger, 41 older infants) revealed that arousal levels were highest for the talking reunion, lowest for unfamiliar songs, and intermediate for familiar songs. The arousal effects, considered in conjunction with the behavioral effects, confirm that songs are more effective than speech at mitigating infant distress. We suggest, moreover, that familiar songs generate higher infant arousal than unfamiliar songs because they evoke excitement, reflected in modestly elevated arousal as well as pleasure, in contrast to more subdued responses to unfamiliar songs.

Infants relax in response to unfamiliar foreign lullabies

“…These findings support a hypothesized role for infant-directed song in the ecosystem of parental investment 21,22 -including the proclivity of parents to sing to their infants [5][6][7] ; the acoustic features that characterize infant-directed songs worldwide 1,34,[40][41][42][43][44][45] ; infants' ability to perceive them and motivation to engage with them 63,64 ; and their calming effects [48][49][50][51] -that is both universal and innately specified.…”

“…Whether the relaxation effects reflect infants' predispositions, early learning, or both, two aspects of infants' responses to music are surprising. First, whereas prior work has demonstrated effects of music on infant arousal 49,50 , they were likely bolstered by mere-familiarity effects 47 , as infants have robust preferences for familiar, positive experiences. Here, because infants were unfamiliar with all aspects of the lullabies (including the languages in which they were sung and the societies in which they were recorded) the results imply a specific soothing effect of music, over and above any potential effects of familiarity.…”

“…Second, we analyzed infants' electrodermal activity, an indicator of arousal used in prior studies of relaxation responses to music 48,50 . If the lullabies relaxed infants, then electrodermal activity should decrease during lullabies, relative to non-lullabies.…”

“…First, we noted an overall positive trend in electrodermal activity throughout the study, irrespective of the songs the infant was listening to. We fit a random-effects linear model to all z-scored observations (N = Note that this result contrasts sharply with infants' responses during a distress induction procedure, as in previous research on the calming effects of singing 50 . In that type of study, arousal and fussiness increase during a negative interaction (e.g., a still-face procedure), and subsequently decrease during a positive "recovery phase".…”

Acoustic regularities in infant-directed speech and song across cultures

“…This idea is supported by at least three forms of evidence. First, infant-directed song modulates infant arousal, whether the songs are familiar 50 or not 51 , and delays the onset of infant distress longer than does infant-directed speech 52 . Second, people with genomic imprinting disorders, which are characterized by altered parental investment behaviors, such as those related to food consumption 53,54 , also have altered music perception ability and responses to music 55,56 .…”