Development of approach and inhibition in the first year: parallel findings from motor behavior, temperament ratings and directional cardiac response

A group of 139 infants was observed at 6 and 12 months. Approach and inhibition were measured via latencies to touch lowand high-intensity objects, directional cardiac response to lowand high-intensity sounds and maternal ratings of positive and fearful emotionality. Inhibition showed considerable increases in all three domains from 6 to 12 months. Also reflecting increases in inhibitory processes, correlations between individual infants’ responses to lowand high-intensity sounds were significantly smaller at 12 than at 6 months. Limited cross-domain validity was obtained linking large cardiac decelerations, low latencies to reach for toys and high ratings of positive emotionality. These findings are consistent with previous reports documenting relatively greater gains in inhibition than approach during the second half of the first year. Modest cross-domain consistency indicates separate mechanisms may moderate approach and inhibition in the three different realms.