Verbal Declarative Memory Dysfunction in Schizophrenia: From Clinical Assessment to Genetics and Brain Mechanisms

The recent literature on the neuropsychology of schizophrenia has emphasized memory deficits as a key area of impairment. Abnormalities in the medial temporal lobe, a brain region crucial for long-term memory formation, have also consistently been reported. We conducted a comprehensive review of verbal declarative memory (VDM) in schizophrenia with the aim of systematically addressing the nature of this impairment. We conclude that verbal declarative memory is significantly impaired in schizophrenia and is largely accounted for by deficits in the encoding stage. Subtle impairments in increased rates of forgetting are present, but are mild compared with those in amnestic disorders. Impairment in other cognitive domains studied thus far (e.g., attention), medication effects, or fluctuations in symptoms do not completely account for the deficit. VDM is among the most impaired neurocognitive domains in schizophrenia (along with attention and executive functions). Milder encoding deficits are present in high-risk subjects and non-psychotic relatives of individuals with schizophrenia suggesting that components of the deficit are associated with a genetic vulnerability to the illness, and are independent of the frank psychotic illness. Furthermore, VDM is observed in individuals experiencing their first-psychotic episode and it remains fairly consistent over time. Preliminary imaging studies and other work suggest abnormalities in prefrontal-hippocampal processing networks. Future work should emphasize delineating specific information processing components contributing to the deficit. This would allow imaging studies to determine which brain regions contribute to specific information processing deficits in schizophrenia.     

文本阅读中信息的协调性整合

根据文本阅读双加工理论的主要观点, 研究者提出了“协调性整合”这一信息加工形式, 然后通过设计一系列的实验, 系统探讨了文本阅读中协调性整合的性质、过程和条件等内容, 这些研究成果验证并支撑了文本阅读双加工理论的核心观点, 进一步丰富了文本阅读双加工理论的内容, 推动了文本阅读研究的进一步发展。     

眼睛注视线索提示效应: 内源性注意还是外源性注意?

采用改进的Posner视-空间线索提示范式, 对眼睛注视线索提示效应(eyes gaze cueing effect)的加工机制进行了探讨。实验一考察注视提示线索对空间Stroop效应的影响; 实验二考察注视提示线索对特征抽取和特征整合的影响。实验结果显示: 注视线索提示有效时的空间Stroop效应显著大于提示无效的情景; 在单一特征搜索与特征联合搜索任务中, 注视线索提示效应无差别。这说明, 注视线索通过在头脑里形成空间方位表征诱导注意转移; 注视线索通过影响特征抽取、而非特征整合阶段, 对客体加工产生易化。本研究支持注视线索提示效应属于内源性注意的观点。     

社会认知具有更强的内隐性──兼论内隐和外显的“钢筋水泥”关系

采用Ｊａｃｏｂｙ的加工分离程序,对记忆测验中图片的社会性特征与非社会性特征的外显记忆现人隐记忆贡献进行分离,考察了对社会性信息的加工中内隐记忆的贡献是强于对非社会性信息加工的内隐记忆贡献,还是相反。结果表明：对社会性信息的加工中内隐记忆的贡献强于对非社会性信息加工的内隐记忆贡献。另外在本实验研究结果的启发下,提出了内隐和外显记忆的“钢筋水泥”结构性模型的假设。     

Attention allocation and habituation to anger-related stimuli during a visual search task

A substantial amount of data has accumulated demonstrating that emotionally disordered subjects are prone to bias their attention toward threatening, emotionally relevant stimuli. Little attention has been reserved for the study of cognitive processes involved in anger arousal. In the present study, we investigated whether mood-congruent attentional biases could be demonstrated in subjects of varying levels of trait anger using a visual search task. This task also assessed whether mood-congruent biases diminished with repeated exposure to specific emotion stimuli. To investigate state-trait interaction effects, a naturalistic, anger-inducing insult was administered to half the subjects. There was a positive relation between participants' level of trait anger and their degree of mood-congruent attentional bias toward anger-related cues only after an insult. As predicted, this effect diminished across blocks of trials. Aggr. Behav. 24:399–409, 1998. © 1998 Wiley-Liss, Inc.     

Compatibility and the use of information processing strategies

When a prominent attribute looms larger in one response procedure than in another, a violation of procedure invariance occurs. A hypothesis based on compatibility between the structure of the input information and the required output was tested as an explanation of this phenomenon. It was also compared with other existing hypotheses in the field. The study had two aims: (1) to illustrate the prominence effect in a selection of preference tasks (choice, acceptance decisions, and preference ratings); (2) to demonstrate the processing differences in a matching procedure versus the selected preference tasks. Hence, verbal protocols were collected in both a matching task and in subsequent preference tasks. Silent control conditions were also employed. The structure compatibility hypothesis was confirmed in that a prominence effect obtained in the preference tasks was accompanied by a lower degree of attention to the attribute levels in these tasks. Furthermore, as predicted from the structure compatibility hypothesis, it was found that fewer comparisons between attribute levels were performed in the preference tasks than in the matching task. It was therefore concluded that both these processing differences may explain the occurrence of the prominence effects. © 1998 John Wiley & Sons, Ltd.     

Maternal responsiveness and search for hidden objects and contingency learning by infants

The relationship between maternal responsiveness and infant cognition was examined during two activities: the search for hidden objects and the learning of a contingency rule. Thirty-four mother–infant dyads were observed in a laboratory setting when the infants were 11 months old. The experimental session included three phases: a search for hidden objects (Piagetian tasks), the learning of a contingency rule on a touch screen, and a mother–infant play session using a standardised toy. The results indicated a link between performances in the search and contingency tasks. Moreover, infants who succeeded in both tasks had mothers who displayed higher responsiveness score. The findings are discussed in terms of the infant's detection of relevant stimulus information. © 1998 John Wiley & Sons, Ltd.     

离散还是连续?——语义信息加工性质的实验研究

通过两个行为实验,采用句子核证作业,将SAD技术和普通反应时实验有机地结合起来,对语义信息加工的性质进行了详细的考察。实验一采用普通反应时实验,探讨了语义信息加工机制的性质,结果表明,在熟悉度、语义距离和快慢反应时之间存在复杂的交互作用,说明在语义信息加工中存在两种不同性质的加工机制,熟悉性是影响这两种不同性质加工机制的因素。实验二采用SAD技术,研究熟悉性对语义信息加工性质的影响。结果表明,在高熟悉句中的部分信息积累具有离散的趋势;而低熟悉句中的部分信息积累则是连续的,进一步证明了两种性质加工机制的存在。结论认为：语义信息加工中存在着两种性质的加工：离散性加工机制和连续性加工机制,熟悉性是影响二者关系的一个重要因素。     

篇章阅读理解中背景信息的通达

该研究采用实时窗口阅读技术探讨篇章阅读理解中背景信息的通达机制。在该研究所用的阅读材料中,主人公特征与目标句行为分别形成一致、冲突与冲突限制三种关系,其中,冲突限制条件下既描述了主人公与目标行为有所冲突的特征,但这些特征要么是主人公过去具有的、要么是虚假的,在此基础上,阅读材料又提供了主人公当前的、与目标句行为一致的特征描述。结果发现,不论把冲突限制条件下的冲突信息限制在过去发生,还是作为一种虚假的情况来加以描述,都不能完全消除冲突的效应,冲突限制条件下目标句阅读时间总是长于一致条件下的阅读时间,这支持了记忆基础文本加工观,说明在篇章阅读中背景信息通达不是一个更新追随的过程,过去的或虚假的背景信息也会被重新激活并影响当前信息的加工。     

Motivations, Goals, Information Search, and Memory about Political Candidates

This study investigated the ways in which motivations and goals affect patterns of political information-seeking and the consequent structure of memory about candidates. Undergraduate participants used a computerized system that displayed different layers of information about fictional political candidates; the system recorded the strategies they used to search through this information. Results showed that motivations to engage in effortful processing produced tendencies to engage in within-candidate searches, better recall, and memory structures clustered by candidate. The goal of forming impressions of the candidates, which was expected to lead to within-candidate searching, was in fact modestly associated with weaker tendencies to do so, once effort was taken into account. Impression-formation goals, however, were associated with less attribute-based memory structures. The findings confirm that the manner in which people acquire candidate information has important consequences for the way they store that information in memory, and that these processes vary according to individual motivations and goals.