Prerequisites for lack of age differences in memory performance.

Free recall performance of young and old adults was examined in three memory tasks: acts carried out by the subjects (subject-performed tasks or SPTs), sentences with imagery instructions, and sentences. The subjects were presented with the same verbal information in all three tasks. No age differences were observed on free recall of SPTs, whereas typical aging effects were obtained on free recall of the other tasks. This way the data from a previous study of no age effects on SPT recall were replicated. A hypothesis about imagery as a critical factor for the lack of age differences on SPT recall gained no support. Two main concepts were proposed to account for the data: Compensation among the elderly by means of the multimodal and rich properties of SPTs, and a superior ability for a spontaneous recoding of verbal information among young adults. The results were also discussed in relation to a presumption of memory tasks as varying in attentional demands.