Coordinated interpersonal timing in adult-infant vocal interactions: A cross-site replication

Coordinated interpersonal tinning exists when the temporal pattern of each partner in a dialogue is predictable from that of the other. Using a completely automated microanalytic technique to time the sequence of vocal sounds and silences in an interaction, we studied 28 four-month-old infants in face-to-face play with mother and a female stranger. Fifteen infants were recorded on one site and 13 at another. Time-series regression was used to evaluate the direction and magnitude of interpersonal prediction. Results indicated that (a) significant coordination (or its absence) occurred at both sites for 90% of the comparisons, and (b) the lag that best predicted the partner was 20 to 30 s at both sites. Unlike the labor-intensive microanalytic coding techniques that have dominated mother-infant interaction research, this work has the following advantages: (a) the automated instrumentation times behavior with a precision unobtainable by the unaided human observer; (b) the sound-silence variables are unambiguously defined for computer processing; and (c) the microanalytic method is applicable to large-sample studies. This automated method has shown its clinical utility in its power to predict 1-year developmental outcomes from 4-month coordinated interpersonal timing.