The choose-short effect and trace models of timing

The tuned-trace multiple-time-scale (MTS) theory of timing can account both for the puzzling choose-short effect in time-discrimination experiments and for the complementary choose-long effect. But it cannot easily explain why the choose-short effect seems to disappear when the intertrial and recall intervals are signaled by different stimuli. Do differential stimuli actually abolish the effect, or merely improve memory? If the latter, there are ways in which an expanded MTS theory might explain differential-context effects in terms of reduced interference. If the former, there are observational and experimental ways to determine whether differential context favors prospective encoding or some other nontemporal discrimination.     

Animal models of source memory

Source memory is the aspect of episodic memory that encodes the origin (i.e., source) of information acquired in the past. Episodic memory (i.e., our memories for unique personal past events) typically involves source memory because those memories focus on the origin of previous events. Source memory is at work when, for example, someone tells a favorite joke to a person while avoiding retelling the joke to the friend who originally shared the joke. Importantly, source memory permits differentiation of one episodic memory from another because source memory includes features that were present when the different memories were formed. This article reviews recent efforts to develop an animal model of source memory using rats. Experiments are reviewed which suggest that source memory is dissociated from other forms of memory. The review highlights strengths and weaknesses of a number of animal models of episodic memory. Animal models of source memory may be used to probe the biological bases of memory. Moreover, these models can be combined with genetic models of Alzheimer's disease to evaluate pharmacotherapies that ultimately have the potential to improve memory.     

Memory in pregnancy and post‐partum: Item specific and relational encoding processes in recall and recognition

It has been recently proposed that pregnant women would perform memory tasks by focusing more on item‐specific processes and less on relational processing, compared to post‐partum women (Mickes, Wixted, Shapiro & Scarff, 2009 ). The present cross‐sectional study tested this hypothesis by directly manipulating the type of encoding employed in the study phase. Pregnant, post‐partum and control women either rated the pleasantness of word meaning (which induced item‐specific elaboration) or named the semantic category to which they belonged (which induced relational elaboration). Memory for the encoded words was later tested in free recall (which emphasizes relational processing) and in recognition (which emphasizes item‐specific processing). In line with Mickes et al.'s ( 2009 ) conclusions, pregnant women in the item‐specific condition performed worse than post‐partum women in the relational condition in free recall, but not in recognition. However, compared to the other two groups, pregnant women also exhibited lower recognition accuracy in the item‐specific condition. Overall, these results confirm that pregnant women rely on relational encoding less than post‐partum women, but additionally suggest that the former group might use item‐specific processes less efficiently than post‐partum and control women.     

List-method directed forgetting: Evidence for the reset-of-encoding hypothesis employing item-recognition testing

In list-method directed forgetting (LMDF), people are cued to forget a previously studied item list (List 1) and to learn a new list of items (List 2) instead. Such cuing typically enhances memory for the List 2 items, in both recall and (sometimes) item-recognition testing. It has recently been hypothesized that the enhancement effect for List 2 items (partly) reflects the result of a reset-of-encoding process. The proposal is that encoding efficacy decreases with an increase in study material, but the forget cue can reset the encoding process to make the encoding of early List 2 items as effective as the encoding of early List 1 items. An experiment is reported that examined the reset-of-encoding hypothesis with item-recognition testing, examining influences of items' serial learning position on the effects of the forget cue. Item-recognition tests were conducted separately for the two lists. Consistent with the reset-of-encoding hypothesis, the results showed strong enhancement effects for early List 2 items, but hardly any enhancement effects for middle and late List 2 items. Like in previous item-recognition studies, no cuing effects were found for List 1 items. The results support two-mechanism accounts of LMDF, which assume a critical role for a reset-of-encoding process for List 2 enhancement.     

基于自我参照编码的复合反应范式：有效鉴别有罪者和无罪知情者

隐藏信息测试在司法实践中应用受限的主要原因是容易将知道犯罪相关信息的无罪知情者误判为有罪者, 因此, 需探索有效区分有罪者和无罪知情者、有罪者和无罪不知情者的测谎技术。复合反应范式(complex trial protocol, CTP)是一种能有效抵抗反测谎的隐藏信息测试, 但尚未成功用于鉴别有罪者和无罪知情者。本研究设计了可同时测量EPN和P300的基于自我参照编码的CTP, 每个试次的第一部分随机呈现探测刺激或无关刺激, 第二部分随机呈现目标刺激(自己姓名)或非目标刺激(他人姓名), 要求被试在两个部分看到刺激时均做“与我有关”和“与我无关”的反应。结果表明, 基于自我参照编码的CTP能有效区分有罪者和无罪知情者, EPN区分有罪者和无罪知情者的鉴别力优于P300, P300区分有罪者和无罪不知情者的鉴别力优于EPN。     

认知负荷与编码方式对前瞻记忆及其成分的影响

实验1探究认知负荷（高、低）与编码方式（标准、书写、执行意向）对前瞻记忆的影响,实验2进一步探究其对前瞻记忆两种成分的影响。实验1显示执行意向与书写编码的正确率高于标准编码,而前二者无差异;低负荷的前瞻记忆表现好于高负荷。实验2显示执行意向与书写编码的前瞻成分正确率高于标准编码,而前二者无差异;低负荷的前瞻成分表现好于高负荷;不同认知负荷与编码方式均对回溯成分无影响。结果表明：在意向内容相对简单的情况下,执行意向与书写编码对前瞻记忆的促进作用主要表现在促进前瞻成分的提取,低负荷比高负荷有利于前瞻记忆的成功执行,主要体现在前瞻成分成功率更高。     

Gesturing helps memory encoding in aMCI

Encoding in episodic memory is a step often impaired in patients with amnestic Mild Cognitive Impairment (aMCI). However, procedural memory processes are still relatively preserved. In line with previous research on the enactment effect, we investigated the potential benefit of encoding words combined with imitative gestures on episodic memory. Based on the Grober and Buschke’s free/cued recall procedure, we developed the Symbiosis test in which 13 patients with aMCI and 16 healthy elderly participants learned 32 words belonging to 16 different semantic categories either in a verbal encoding (A) or a bimodal (B; verbal and motor imitation) condition, using a blocked ABBA/BAAB procedure. Overall, memory retrieval was better in healthy participants than in patients with aMCI, and better for cued retrieval in the bimodal encoding (gesture cues) than the verbal encoding (category cues) condition, but there was no interaction effect between group and encoding conditions. These results show that performing concomitant gestures can enhance cued episodic memory retrieval in patients with aMCI and in healthy elderly controls. The Symbiosis test broadens the scope of the enactment effect, from action phrases to isolated words learning in patients with aMCI. Future work should investigate how bimodal encoding provides novel perspectives for memory rehabilitation in patients with aMCI.     

The role of grammatical class on word recognition

The double dissociation between noun and verb processing, well documented in the neuropsychological literature, has not been supported in imaging studies. Recent imaging studies, in fact, suggest that once confounding with semantics is eliminated, grammatical class effects only emerge as a consequence of building frames. Here we assess this hypothesis behaviorally in two visual word recognition experiments. In Experiment 1, participants made lexical decisions on verb targets. We manipulated the grammatical class of the prime words (either nouns or verbs and always introduced in a minimal phrasal context, i.e., “the + N” or “to + V”), and their semantic similarity to a target (related vs. unrelated). We found reliable effects of grammatical class, and no interaction with semantic similarity. Experiment 2 further explored this grammatical class effect, using verb targets preceded by semantically unrelated verb vs. noun primes. In one condition, prime words were presented as bare words; in the other, they were presented in the minimal phrasal context used in Experiment 1. Grammatical class effects only arose in the latter but not in the former condition thus providing evidence that word recognition does not recruit grammatical class information unless it is provided to the system.     

Sex-contingent face aftereffects depend on perceptual category rather than structural encoding

Many studies have used visual adaptation to investigate how recent experience with faces influences perception. While faces similar to those seen during adaptation phases are typically perceived as more 'normal' after adaptation, it is possible to induce aftereffects in one direction for one category (e.g. female) and simultaneously induce aftereffects in the opposite direction for another category (e.g. male). Such aftereffects could reflect 'category-contingent' adaptation of neurons selective for perceptual category (e.g. male or female) or 'structure-contingent' adaptation of lower-level neurons coding the physical characteristics of different face patterns. We compared these explanations by testing for simultaneous opposite after effects following adaptation to (a) two groups of faces from distinct sex categories (male and female) or (b) two groups of faces from the same sex category (female and hyper-female) where the structural differences between the female and hyper-female groups were mathematically identical to those between male and female groups. We were able to induce opposite aftereffects following adaptation between sex categories but not after adaptation within a sex category. These findings indicate the involvement of neurons coding perceptual category in sex-contingent face aftereffects and cannot be explained by neurons coding only the physical aspects of face patterns.     

二年级小学生“记”“忆”策略的微观发生研究

采用微观发生法,以33名小学二年级学生为被试,以记忆书面语词的分类材料为任务,对儿童记忆过程中"记"、"忆"策略的不同发展规律进行了5个期间的测查.结果发现:(1)分类记忆策略的发展既有突变过程也有渐变过程:分类记策略有生成缺陷,表现为训练后的突然变化;分类忆策略则是一个可以自发形成的渐变过程,如果加以适当的训练也会发生突然的增长.(2)在材料熟悉度较低的情况下,会使少量儿童产生分类记、忆策略使用缺陷现象.