Formal reasoning in late adulthood: The role of semantic content and metacognitive strategy

Two experiments explored the availability of deductive or formal reasoning in late adulthood. In Experiment 1, fifty young (M=19.0 years) and 50 elderly adults (M=81.0 years) were assessed using adaptations of Wason's selection task and rated task content for familiarity, affect, and agreement. In Experiment 2, 100 young (M=21.0 years) and 100 elderly adults (M=81.0 years) were similarly assessed, with half of the subjects in each age group receiving a metacognitive strategy to facilitate reasoning. Results from Experiment 1 indicated equivalent reasoning among the groups on problems employed in earlier developmental research. In contrast, problems constructed to entail affect resulted in poorer performance by older adults. In Experiment 2, both young and older adults who used the metacognitive strategy reasoned equally acrossall problems. In both experiments, familiarity and agreement did not play a role in deductive reasoning performance, but affect seemed to be an interfering factor. Results are discussed in terms of competence-procedure and stability-decrement models of adult cognitive development.     

Psychobiological evidence for the distinction between episodic and semantic memory

The evidence for discrete neurobiological mechanisms that underlie episodic and semantic memory is reviewed. Published data from three separate lines of research are considered: studies of human amnesic patients, psychopharmacological studies of normal human subjects, and studies of working and reference memory in rodents, a distinction that is arguably analogous to the episodic/semantic dichotomy. It is concluded that the available evidence does not indicate that episodic and semantic memory are mediated by discrete neural subsystems. An alternative model of human memory is discussed, based on the concept of parallel distributed processing.An earlier version of this paper was submitted as part of the author's qualifying examination at Emory University.     

The attribute priming effect in patients with Alzheimer's disease

Experiments with semantic priming (SP) paradigms have documented early hypopriming in patients with AD when concepts are used as primes and attribute concept features as targets, suggesting that concept attributes are vulnerable to damage very early in the disease course. The aims of this study were to confirm early priming reduction in the attribute condition in patients with AD and to determine which of several semantic indexes (such as the level of distinctiveness, correlation or feature dominance of concept features) best predicts the priming effect size in AD. We administered an SP attribute condition paradigm to 20 mildly demented patients with AD and to 10 NCs. We used concept–attribute pairs for which normative data of semantic indexes relative to both concept primes (i.e., number, type, mean level of dominance, distinctiveness and correlation of features constituting the concepts) and target features (i.e., level of feature dominance, correlation and distinctiveness) were available. Results showed that compared to NCs, the AD group obtained very reduced priming facilitation. Furthermore, the item regression analyses showed that the priming decrement in the AD group was predicted by the feature dominance of the target in the related pairs; that is, the lower the target feature dominance, the lower the priming effect elicited. These results confirmed hypopriming in the attribute condition from the very early phase of AD and support the view that attributes which are more salient for the identification of a given concept are also those most resistant to semantic memory degradation in AD pathology.     

Mechanical knowledge does matter to tool use even when assessed with a non-production task: Evidence from left brain-damaged patients

In the literature on apraxia of tool use, it is now accepted that using familiar tools requires semantic and mechanical knowledge. However, mechanical knowledge is nearly always assessed with production tasks, so one may assume that mechanical knowledge and familiar tool use are associated only because of their common motor mechanisms. This notion may be challenged by demonstrating that familiar tool use depends on an alternative tool selection task assessing mechanical knowledge, where alternative uses of tools are assumed according to their physical properties but where actual use of tools is not needed. We tested 21 left brain-damaged patients and 21 matched controls with familiar tool use tasks (pantomime and single tool use), semantic tasks and an alternative tool selection task. The alternative tool selection task accounted for a large amount of variance in the single tool use task and was the best predictor among all the semantic tasks. Concerning the pantomime of tool use task, group and individual results suggested that the integrity of the semantic system and preserved mechanical knowledge are neither necessary nor sufficient to produce pantomimes. These results corroborate the idea that mechanical knowledge is essential when we use tools, even when tasks assessing mechanical knowledge do not require the production of any motor action. Our results also confirm the value of pantomime of tool use, which can be considered as a complex activity involving several cognitive abilities (e.g., communicative skills) rather than the activation of gesture engrams.     

ERP与语言研究

语言加工是连续的、具有多个分析层次的复杂过程。而新近发展起来的ERP技术具有精确的时间分辨率和多维探测指标,可以对语言进行连续的测量,同时对不同层次的分析有不同的敏感指标。该文着重介绍了与语音层次加工有关的ERP成分N200,与语义加工相关的RP和N400,以及与句法加工有关的LAN和P600,以期为语言领域的ERP研究提供启发和帮助作用。     

句子加工中语义关联性和句法歧义性实验研究

采用自定速移动视窗技术,探讨语义关联性和句法歧义性对汉语直接宾语、宾语小句类暂时句法歧义句理解加工的影响。结果发现：语义关联性和句法歧义性对歧义区和解歧区的阅读时间有显著影响,并在解歧区产生了显著的交互作用,表明语义信息即时参与对句子的理解加工并同句法信息一起共同影响句子的认知加工过程。     

句子背景下缺失音素的中文听觉词理解的音、义激活进程（Ⅱ）

采用缺失音素的中文双字词为材料,进一步考察了中文听觉词的语音、语义激活进程。共包含两个实验：实验1考察听觉词语音能否同时激活多个与之语音相近的语音、语义结点;实验2考察在听觉词词汇提取后期,是否还存在语音的激活作用。结果表明：⑴中文听觉词的语音能够同时激活与之语音相近的语音、语义结点,这种语音作用在ISI=400ms时处于较低水平;⑵听觉词呈现结束后,语音存在着二次激活现象;⑶对缺失声母的中文听觉词理解后期,除语义背景依赖效应外,还存在明显的语音作用,两者共同作用共同实现对目标词的语义恢复。根据对句子背景下缺失声母的中文听觉词理解的实验结果,作者提出了“中文听觉词理解的激活扩散动态模型”。     

创造性思维中语义搜索过程：基于答案累积时间函数和语义相似性的量化分析

通过描绘发散性思维测验(物品多用途, AUT)中答案生成在累积函数和语义相似性等一系列参数上的量化特征, 揭示创造性思维的语义搜索过程。结果发现：(1)新颖AUT条件中, 语义搜索呈现与自由联想类似的负加速特点, 但搜索速度较寻常AUT条件更慢。(2)新颖AUT条件中所生成的答案与题目(即物品)均具有较低的语义相似性, 且显著小于寻常AUT条件。(3)新颖AUT条件中生成的答案比寻常AUT条件表现出显著更低的聚类程度, 其中可聚类答案和未聚类答案与题目的语义相似度均较低, 且不存在显著差异, 二者在新颖性上也不存在显著差异。以上结果说明了创造性思维的语义信息搜索过程具有与自由联想类似的激活扩散特征, 但总体搜索速度较慢。新颖性要求使得个体在最初搜索时便开始摆脱题目的语义限制而进行远距离搜索(避免就近搜索), 并倾向于在每个语义场中只生成一个答案(避免局部搜索), 但也可能会在远离题目的语义场中生成多个同类别答案。     

声符与义符在形声字识别中的影响机制

形声字是汉字的主体,声符和义符作为形声字的构字部件,其各自的功能属性对形声字的识别具有不同的影响。当前研究采用多种实验任务,结合眼动以及脑电等多种技术,对声符和义符各自的功能属性及作用机制进行了较为全面的研究,这为后续研究奠定了良好的基础,并对未来汉字认知领域的研究具有重要的启示作用。     

负性情绪对不同语义、空间关系联结记忆的影响

以负性项目-中性场景以及中性项目-中性场景组成的图片对为材料,通过操控项目-场景之间的语义联系和空间距离,考察了负性情绪对不同语义、空间关系联结记忆的影响。结果显示,当项目-场景空间距离较近时,无论项目-场景之间的语义是否相关,负性情绪始终不会影响项目-场景联结记忆;当项目-场景空间距离较远且语义不相关时,负性情绪会削弱项目-场景联结记忆;而当项目-场景空间距离较远且语义相关时,负性情绪会促进项目-场景联结记忆。结果表明,负性情绪对项目-场景联结记忆的影响会受到项目与场景之间语义关系和空间关系的调节,且语义关系在项目-场景空间距离较远时的作用更为突出。