Department of Psychology, University of Warwick.
Dev Psychol. 2013 Dec;49(12):2396-404. doi: 10.1037/a0032272. Epub 2013 Apr 15.
Three alternative mechanisms for age-related decline in memory search have been proposed, which result from either reduced processing speed (global slowing hypothesis), overpersistence on categories (cluster-switching hypothesis), or the inability to maintain focus on local cues related to a decline in working memory (cue-maintenance hypothesis). We investigated these 3 hypotheses by formally modeling the semantic recall patterns of 185 adults between 27 to 99 years of age in the animal fluency task (Thurstone, 1938). The results indicate that people switch between global frequency-based retrieval cues and local item-based retrieval cues to navigate their semantic memory. Contrary to the global slowing hypothesis that predicts no qualitative differences in dynamic search processes and the cluster-switching hypothesis that predicts reduced switching between retrieval cues, the results indicate that as people age, they tend to switch more often between local and global cues per item recalled, supporting the cue-maintenance hypothesis. Additional support for the cue-maintenance hypothesis is provided by a negative correlation between switching and digit span scores and between switching and total items recalled, which suggests that cognitive control may be involved in cue maintenance and the effective search of memory. Overall, the results are consistent with age-related decline in memory search being a consequence of reduced cognitive control, consistent with models suggesting that working memory is related to goal perseveration and the ability to inhibit distracting information.
三种与年龄相关的记忆搜索衰退的机制已经被提出，它们分别源于处理速度的降低（整体减速假说）、对类别过度坚持（聚类切换假说），或者无法保持对与工作记忆衰退相关的局部线索的关注（线索维持假说）。我们通过在动物流畅性任务（Thurstone，1938）中正式模拟 185 名年龄在 27 至 99 岁之间的成年人的语义回忆模式，研究了这 3 种假说。结果表明，人们在全局基于频率的检索线索和局部基于项目的检索线索之间切换，以导航他们的语义记忆。与全局减速假说预测动态搜索过程没有定性差异和聚类切换假说预测检索线索之间的切换减少相反，结果表明，随着年龄的增长，人们在每次回忆项目时倾向于更频繁地在局部和全局线索之间切换，支持线索维持假说。线索维持假说的额外支持来自于切换和数字跨度分数之间以及切换和总项目回忆之间的负相关，这表明认知控制可能涉及线索维持和记忆的有效搜索。总的来说，结果与记忆搜索随年龄增长而衰退是认知控制降低的结果一致，与工作记忆与目标坚持和抑制分心信息的能力相关的模型一致。
