The Aging Effect On False Memories In The DRM Paradigm

The aging effect on false memories refers to the phenomena in which older adults are sometimes more likely than younger adults to remember events that never happened or words that never presented to them. The aging effect on false memories has been the concern of many researchers all along, however, the influencing factors and the underlying mechanism of this effect are still under exploration.In this study, five experiments were employed to investigate the aging effect on false memories in the DRM paradigm. In experiment1, the presentation duration of each word of the word-lists was set at1second or3seconds to examine whether the encoding duration would influence this effect. The result showed that true recognitions of studied words by old adults and young adults both increased with the increasing duration,and that old adults’true recognition rate were significantly lower than that of young adults. Meanwhile, when the presentation duration of word-lists was set at1second, we found there were no significant difference between the false recognition rates of critical lures by the two age groups, but when the duration was set at3seconds, the difference turned out to be significant, thus the aging effect on false memories appeared. In experiment2, we introduced warning condition before word-studying phase. It was found that warning had no significant effect on the true recognition rates of studied words by both age groups, neither on the false recognition rates of critical lures by the elder. The warning, however, significantly reduced the false recognition rates of the young, and these rates were significantly lower than those of the elder.In experiment3, we added five minutes delay between the study phase and the test phase, in order to investigate whether aging effects on false memories would be influenced by the interference of the delay. The results, however, showed that the delay had no significant effect on the true or false recognition rates of both age groups. Experiment4and experiment5examined the aging effect on false memories during retrieval stage. In experiment4, we changed the shape, size and color of those presented words in the test phase, so as to explore whether the changes of verbatim traces would influence the aging effect. We found that, changes of verbatim traces have no significant effect on the true recognition rates of both age groups, but the difference between the false recognition rates of the two age groups disappeared with these changes.In experiment5, we burrowed into the influence of time pressure in recognition, and found that the true recognition rates of studied words by the old and the young were both subject to the time pressure and showed significant decreases. Meanwhile, the young subjects’false recognition showed a significant increase, whereas the old subjects had no such change.In summary, this study found that the aging effect on false memories was susceptible to relevant factors in both the encoding stage and the retrieval stage, while in the storing stage, this effect was relatively stable. In the encoding stage, old adults were inefficient of item-specific encoding for studied items, and in the retrieval stage, they relied heavyly on the gist traces of word-lists, as a result, they usually couldn’t manage to suppress the interference of critical lures in many cases. Compared to young adults, they often showed greater level of false recognitions of items not presented to them.