Rhythms of dialogue in infancy: coordinated timing in development.
Although theories of early social development emphasize the advantage of mother-infant rhythmic coupling and bidirectional coordination, empirical demonstrations remain sparse. We therefore test the hypothesis that vocal rhythm coordination at age 4 months predicts attachment and cognition at age 12 months. Partner and site novelty were studied by recording mother-infant, stranger-infant, and mother-stranger face-to-face interactions in both home and laboratory sites for 88 4-month-old infants, for a total of 410 recordings. An automated dialogic coding scheme, appropriate to the nonperiodic rhythms of our data, implemented a systems concept of every action as jointly produced by both partners. Adult-infant coordination at age 4 months indeed predicted both outcomes at age 12 months, but midrange degree of mother-infant and stranger-infant coordination was optimal for attachment (Strange Situation), whereas high ("tight") stranger-infant coordination in the lab was optimal for cognition (Bayley Scales). Thus, high coordination can index more or less optimal outcomes, as a function of outcome measure, partner, and site. Bidirectional coordination patterns were salient in both attachment and cognition predictions. Comparison of mother-infant and stranger-infant interactions was particularly informative, suggesting the dynamics of infants' early differentiation from mothers. Stranger and infant showed different patterns of vocal rhythm activity level, were more bidirectional, accounted for 8 times more variance in Bayley scores, predicted attachment just as well as mother and infant, and revealed more varied contingency structures and a wider range of attachment outcomes. To explain why vocal timing measures at age 4 months predict outcomes at age 12 months, our dialogue model was construed as containing procedures for regulating the pragmatics of proto-conversation. The timing patterns of the 4-month-olds were seen as procedural or performance knowledge, and as precursors of various kinesic patterns in the outcomes of 12-month-olds. Thus, our work further defines a fundamental dyadic timing matrix--a system that guides the trajectory of relatedness, informing all relational theories of development.
Jaffe
J
J
College of Physicians & Surgeons, Columbia University, USA.
Beebe
B
B
Feldstein
S
S
Crown
C L
CL
Jasnow
M D
MD
D002657:Child Development / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D006801:Humans; D007223:Infant; D007398:Interpersonal Relations; D009034:Mother-Child Relations; D009769:Object Attachment; D010507:Periodicity; D013060:Speech / Q000502:physiology*; D013997:Time Factors; D014705:Verbal Behavior