Episodic memory development: theory of mind is part of re‐experiencing experienced events

Two experiments with 3½‐ to 6½‐year‐old children showed that theory‐of‐mind development is associated with the growth of episodic memory. Episodic memory was assessed by manipulating informational conditions such that they permit or prevent the formation of episodic memories in terms of re‐experiencing the recalled event. Only experienced events, e.g. seeing how one puts a picture of a frog into a box, can be remembered by re‐experience. Events known through indirect information cannot be re‐experienced, e.g. putting pictures into the box when blindfolded and being later shown on video what was on these cards. Children were also tested on a battery of theory‐of‐mind tasks assessing their understanding of the origins of knowledge. There was a significant interaction in both experiments showing that recall of directly experienced items improved in relation to indirectly presented items the higher children's theory‐of‐mind scores. The discussion suggests that episodic memory development is specifically linked to the growing ability to introspect an ongoing experience and interpret it as representing an actual past event. Copyright © 2007 John Wiley & Sons, Ltd.     

自传记忆的加工机制研究进展

自传记忆是关于个人生活经验的记忆,它有悖于Ehbinghaus的记忆研究传统。在国外．90年代以来自传记忆研究已成为继内隐记忆研究后．记忆领域的又一研究热点。自传记忆加工机制的研究是认知心理学对自传记忆研究的核心领域。本文主要评析了自传记忆的知识表征．自传记忆提取机制的研究进展。目前已有的研究结论是：（1）自传记忆是以个人生活片段知识、一般事件知识和具体事件知识三种方式表征的;（2）自传记忆的提取方式主要通过生成提取和直接提取方式来实现。     

记忆提取研究的新进展

该文从3个方面回顾了记忆提取研究领域内的最新进展:(1)记忆编码和提取之间的关系,主要针对提取过程的自动性和控制性及相应的神经机制进行了讨论;(2)基于记忆提取的抑制机制,主要涉及指向性遗忘、提取-练习范式的研究及负启动范式在记忆提取研究中的应用;(3)工作记忆能力与记忆提取之间的关系,主要集中于工作记忆能力与控制性记忆提取及记忆提取中的抑制机制之间的关系。     

Ontogeny of early event memory: I. Forgetting and retrieval by 2- and 3-month-olds

In 2 experiments, 2-month-olds, trained in the mobile conjugate reinforcement paradigm for two daily sessions, showed retrieval deficits relative to 3-month-olds. In Experiment 1, tests of simple forgetting administered to 2-month-olds after retention intervals of 1, 3, 6, and 9 days (a period over which 3-month-olds remember the contingency) indicated that their forgetting was complete after delays greater than 1 day. In Experiment 2, reactivation treatments administered to 2- and 3-month-olds alleviated forgetting after a retention interval of 28, but not 35, days in the 3-month-old group only. Previously, alleviated forgetting by a reactivation treatment had been demonstrated in 2-month-olds after a delay of 18 days. In both of the present experiments, performance of the two age groups did not differ during the immediate retention test at the end of training. These results suggest that neither the age of the infant nor the age of the memory determines memory retrieval after long delays; instead, it appears to be determined by the length of time that a memory has been inaccessible (i.e., forgotten). We propose that factors which delay simple forgetting will correspondingly increase the length of the interval over which a retrieval cue can still be effective in a reactivation paradigm, irrespective of the age of the infant or the age of the memory.     

Mood-dependent retrieval in visual long-term memory: dissociable effects on retrieval probability and mnemonic precision

Although memories are more retrievable if observers’ emotional states are consistent between encoding and retrieval, it is unclear whether the consistency of emotional states increases the likelihood of successful memory retrieval, the precision of retrieved memories, or both. The present study tested visual long-term memory for everyday objects while consistent or inconsistent emotional contexts between encoding and retrieval were induced using background grey-scale images from the International Affective Picture System (IAPS). In the study phase, participants remembered colours of sequentially presented objects in a negative (Experiment 1a) or positive (Experiment 2a) context. In the test phase, participants estimated the colours of previously studied objects in either negative versus neutral (Experiment 1a) or positive versus neutral (Experiment 2a) contexts. Note, IAPS images in the test phase were always visually different from those initially paired with the studied objects. We found that reinstating negative context and positive context at retrieval resulted in better mnemonic precision and a higher probability of successful retrieval, respectively. Critically, these effects could not be attributed to a negative or positive context at retrieval alone (Experiments 1b and 2b). Together, these findings demonstrated dissociable effects of emotion on the quantitative and qualitative aspects of visual long-term memory retrieval.     

Why do older adults have difficulty with semantic fluency?

Aging involves many cognitive declines, particularly in fluid intelligence, with relative maintenance of crystallized intelligence. This paradox is evident in the language domain: lexical retrieval becomes slower and less accurate, despite well preserved vocabularies. Verbal fluency assesses both crystallized and fluid aspects of language. Semantic fluency hypothetically reflects semantic knowledge, while letter fluency putatively reflects executive functioning, which would predict a greater impact of aging on the latter. However, the opposite is typically observed.

To investigate factors contributing to such asymmetries, we examined verbal fluency in 86 adults (30-89 years). Multiple regression analyses indicated that semantic fluency depends largely on lexical retrieval speed, as well as visualization strategies to support controlled retrieval, skills which may disproportionately decline with age. By contrast, letter fluency relies heavily on vocabulary knowledge, providing some protection against age-related declines. These findings contribute to our understanding of the mechanisms of typical age-related declines in word retrieval.     

Self-reference and emotional memory effects in older adults at increased genetic risk of Alzheimer’s disease

The present study investigated whether cognitively healthy older adults who are carriers of the ε4 allele of apolipoprotein E, the most prevalent genetic risk factor for late-onset Alzheimer’s disease, benefit from self-referential processing and emotional processing to the same degree as noncarriers of this gene. Participants encoded emotional and nonemotional narratives using a baseline-orienting task, semantic elaboration, or imagination-based self-referential processing and then completed a recognition memory test. Both groups of older adults showed enhanced recognition memory for narrative information following self-referential processing relative to semantic elaboration, and the magnitude of this memory effect was not affected by ε4 status. However, older adult ε4 carriers did not show an emotional enhancement effect, whereas older adult ε4 noncarriers did. These results indicate that whereas the self-reference effect is not attenuated in cognitively healthy older adults ε4 carriers, deficits in emotional memory may be an early cognitive marker of abnormal decline.     

负性情绪强度对双加工再认提取的影响

双加工理论认为再认提取存在回想和熟悉性两种认知加工过程。本研究采用修正的“记得/知道”范式,考察不同强度的负性情绪对这两种再认提取过程的影响。结果发现：（1）在记得反应上不同负性情绪强度的材料呈现出以下模式：高度负性 > 中度负性 > 轻度负性 > 中性;（2）在知道反应上,不同负性情绪强度的材料呈现出以下模式：中性 > 轻度负性 > 中度负性 > 高度负性。这些结果表明,不同强度的负性材料对情绪记忆的影响表现为两条途径：依赖于回想的再认随着负性情绪强度的增加而逐步提高,另外一个依赖于熟悉性的再认随着负性情绪强度的增加而逐步降低。