The sources of developmental differences in children's incidental processing during discrimination trials

Crane and Ross reported that second graders learned more than sixth graders about attributes made relevant after solution of a discrimination task. Here two experiments are reported that enlighten the sources of this developmental difference. Both make use of an experimental technique whereby children verbalize their hypotheses during solution of a discrimination problem. The results indicate that ten-year-olds do not learn about incidental attributes that they tested while irrelevant in the pre-solution period, but that five-year-olds and seven-year-olds do. Children of all three ages process incidental information about attributes that they did not sample pre-solution. With some qualification, the incidentally processed information is retained throughout a five-minute delay interval. The results bear on developmental trends in the distribution of attention and on theoretical accounts of incidental learning in discrimination tasks.