Life-Span Differences in Memory Integration as a Function of Processing Time

Pezdek reported life-span differences in integration of semantically related pictures and sentences in memory. In this earlier study, sixth-grade and high school subjects spontaneously integrated information across modalities, but third graders and adults over 65 did not integrate this information. The present study extends these findings and tests the hypothesis that the 8-sec presentation rate in the previous study was not sufficient to allow the young children and older adults to perform integration processes in memory. The results were that third graders and older adults (63-78 years) did not integrate pictures and sentences that were presented individually at ah 8-sec rate. However, when the presentation rate was increased to 15 sec per item, cross-modality integration resulted. The , favored interpretation of this result is that the slower presentation rate was necessary for these subjects to actively rehearse different items together, and that this rehearsal strategy is necessary for integration of information in memory. This study clarifies cognitive processing differences at different points in the life span.