Stability of coupled fluctuations in movement and visual attention in infants

Fluctuations in body movement and visual inspection were measured over minu tes in 3-month-old infants to look for evidence of coupling. In Experiment 1, infants (n = 12) looked ad libitum at two identical pictures for an aver age of 7.3 min. Analysis of the spontaneous fluctuations in movement and in spection revealed that they were inversely coupled: Moment-to-moment change s in movement and inspection occurred in opposite directions. In Experiment 2, after 4 min of free looking, infants (n = 33) were presented with a new pair of stimuli, a temporary change in the stimuli, or no change in stimul i. The inverse coupling between the fluctuations in body movement and visua l inspection found in Experiment 1 was present before and after the stimulu s changes, even in infants whose body movement decreased transiently in res ponse to the stimulus changes. The reappearance of inversely coupled fluctu ations in body movement and visual inspection following the stimulus change s was led by increases in movement. The results demonstrate the stability o f the inverse coupling between spontaneous fluctuations in body movement an d visual inspection, and suggest that changes in movement may lead changes in inspection. (C) 2001 John Wiley & Sons, Inc.