想象膨胀范式下错误记忆的老化效应

Imagination inflation effect in older adults

通过2个实验探究想象膨胀范式下老年人的错误记忆特点及其认知机制。实验1采用经典想象膨胀实验范式,考察老年人是否会产生比年轻人更大的想象膨胀错误记忆效应;实验2引入情景特异性诱导技术,进一步考察老年人的想象膨胀错误记忆可能的认知机制。研究结果表明:(1)老年人与年轻人均表现出显著的想象膨胀错误记忆,但老年人并没有比年轻人产生更多的错误记忆;(2)当通过情景特异性诱导技术有效增加了老年人在事件想象过程中的内在细节数量后,老年人的错误记忆显著上升。该结果揭示对事件情景的想象过程是想象膨胀错误记忆发生的关键环节,老年人没有表现出明显的老化效应,主要是由于该群体随年龄增长表现出在回忆/想象情景事件时内部细节缺乏这一特征所致。研究结果支持了建构性情景模拟假说和激活/监测理论。

Most of the studies adopting the Deese/Roediger-McDermott paradigm or misinformation effect paradigm demonstrate that older adults are more susceptible to false memories than young ones. However, whether similar aging effect occurs under the imagination inflation paradigm remains unclear. In this study, two experiments were conducted to explore the imagination inflation effect and its potential underlying mechanism in older adults. In Experiment 1, the classic imagination inflation paradigm was used to investigate whether older adults can induce larger imagination inflation effect than young ones. A 2 × 2 × 2 （age： older adults, young adults × time： pretest, posttest × imagination condition： imagined events, not-imagined events） mixed factorial design was adopted. Owing to their deficit in episodic memory and future simulation, older adults may show less internal （episodic） details than young ones during imagination. We hypothesized that older and young adults show similar false memory effects under the imagination inflation paradigm. In Experiment 2, we used episodic specificity induction technology to further investigate the mechanism of the imagination inflation effect in older adults. Through episodic specificity induction, the number of internal （episodic） details can increase selectively during the imagination of the events, which may facilitate imagination. Therefore, episodic specificity induction brings about larger imagination inflation false memories than control induction. A 2 × 2 × 2 （induction： episodic specificity induction, control induction × time： pretest, posttest × imagination condition： imagined, not-imagined events） mixed design was used in Experiment 2. The procedure of Experiment 2 was similar to that of Experiment 1, except that participants received episodic specificity or control induction before the posttest phase. Results showed that （1） older and young adults experienced significant false memory effect under the imagination inflation paradigm, but older adults did not show more false memories than young adults. （2）Participants who received episodic specificity induction showed more false memories than those who received control induction. Taken together, the results demonstrate that imagination of events plays an important role in producing the imagination inflation effect. The reason that older adults do not show significant higher imagination inflation effect than young ones may be closely related to the lack of internal details during imagination. The imagination inflation effect in older adults may be based on the age-related deficits in episodic memory and future thinking. The results are discussed in terms of activation/monitoring theory and constructive episodic simulation hypothesis.