title: Temporal coordination of arm movements in early infancy: do infants move in synchrony with adult speech?
abstract: The purpose of the present study was to measure the degree of interdependence in timing (a) between infants' right and left arm movements, and (b) between movements of both arms and the onsets of stressed vowels in tape-recorded infant-appropriate speech. Based on previous work concerning closely related phenomena, we hypothesized that both forms of interdependence should be present to a high degree, even very early in infancy. Movements of 2 male and 4 female infants were analyzed at 2 and 10 weeks of age. Videotaping was conducted under 3 conditions: (a) quiet, (b) mother-infant interaction, and (c) presentation of a repeating tape loop containing natural sounding, infant-appropriate speech. Movement events were analyzed using a method of computer-aided 3-dimensional cinematography. A computer algorithm located change-in-direction movement events based on the 3-D coordinates. Lag sequential analysis was used to test for temporal interdependence. No evidence was found for interdependence between right and left arm movements, or between speech events and arm movements. The present findings have important implications for our understanding of early coordination and the regulation of mother-infant interaction. The utility of the movement-scoring methodology is also discussed in terms of its potential application to the study of early coordination development.
mesh_terms: D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007804:Language Development; D008297:Male; D009034:Mother-Child Relations; D009043:Motor Activity; D010700:Phonetics; D013067:Speech Perception; D014705:Verbal Behavior