Developmental changes in endogenous control of attention: the role of target familiarity on infants' distraction latency.

This study evaluated the interactive effects of endogenous and exogenous influences on infants' attention allocation by assessing the role of target familiarity on distraction latency during object exploration. In Experiment 1 (N = 54), infants' distraction latencies as they investigated both familiar toys (ones they previously had seen in a familiarization procedure) and novel toys (ones they had not seen in the familiarization procedure) were assessed longitudinally at 6.5 and 9 months of age. In Experiment 2 (N = 32), infants' distraction latencies were assessed at either 6.5 or 10 months as they investigated either familiar or novel targets. In both experiments, older infants, but not younger infants, exhibited longer latencies as they investigated novel toys as compared with their latencies as they investigated familiar toys. These results are discussed in terms of developmental changes in the interactive effects of endogenous and exogenous factors controlling attention allocation.