Attention and reaction to distress in infancy: a longitudinal study.
The primary aim of this study was to verify whether early individual differences in look duration are related to general mechanisms of the infant nervous system that draw together attention and emotion. Thirty-one infants were observed at 3, 5, and 11 months of age. Facial expressions of pain and distress were observed by means of C. Izard's (1979) Maximally Discriminative Facial Movement Coding System 90 s after routine pediatric vaccinations. Several measures of visual attention were taken experimentally in a separate testing session. Significant correlations between measures of attention and duration of facial expressions of pain and distress were found at each age level. Infants who showed pain or distress for a shorter time period also paid attention for a shorter time period and vice versa. The main conclusion is that individual differences combining control of both pain and attention can be identified from early infancy.