Low working memory capacity is only spuriously related to poor reading comprehension

Accounts of comprehension failure, whether in the case of readers with poor skill or when syntactic complexity is high, have overwhelmingly implicated working memory capacity as the key causal factor. However, extant research suggests that this position is not well supported by evidence on the span of active memory during online sentence processing, nor is it well motivated by models that make explicit claims about the memory mechanisms that support language processing. The current study suggests that sensitivity to interference from similar items in memory may provide a better explanation of comprehension failure. Through administration of a comprehensive skill battery, we found that the previously observed association of working memory with comprehension is likely due to the collinearity of working memory with many other reading-related skills, especially IQ. In analyses which removed variance shared with IQ, we found that receptive vocabulary knowledge was the only significant predictor of comprehension performance in our task out of a battery of 24 skill measures. In addition, receptive vocabulary and non-verbal memory for serial order—but not simple verbal memory or working memory—were the only predictors of reading times in the region where interference had its primary affect. We interpret these results in light of a model that emphasizes retrieval interference and the quality of lexical representations as key determinants of successful comprehension.     

记忆集对注意焦点转换及其返回抑制的影响

采用记忆更新任务,实验1要求被试分别更新3个和4个记忆项目,并设置不转换、控制转换和抑制转换条件,考察记忆集对注意焦点转换及其返回抑制的影响;实验2操纵两次更新同一记忆项目之间对其它记忆项目更新的次数（2次、3次及3次以上）,在实验1基础上,考察返回抑制中项目抑制状态的消退过程.结论：随记忆集增加,转换代价增大,而返回抑制效应消失;当注意焦点对其它记忆项目更新2次时,之前被抑制项目的抑制状态可完全消退.     

Memory of Past Beliefs and Actions

Two notions of memory are studied both syntactically and semantically: memory of past beliefs and memory of past actions. The analysis is carried out in a basic temporal logic framework enriched with beliefs and actions.     

Knowing in advance: the impact of prior event information on memory and event knowledge

We examined the influence of newly acquired information on children's memory and general representation of a personally experienced event. Thirty-five children between the ages of 5 and 7 years participated in the novel event (Visiting the Pirate). The day before participating, children were: (1) provided with new information specific to the up-coming event; (2) engaged in a discussion generally related to the event topic based on existing knowledge; or (3) discussed an unrelated topic. Advance information specific to the event led to better recall and, in particular, to better integration of the experience into a general event representation both soon after the event and at a follow-up interview 4 months later, whereas general discussion of the topic without the event specific information neither enhanced memory reports nor facilitated the integration of event information. Providing information in advance can have significant effects on memory and knowledge acquisition although many variables, including those relating to the specific content of the information, will affect this relation.     

情绪对工作记忆影响的研究综述

情绪在我们的生活中扮演着十分重要的角色,各种认知活动都或多或少的受其影响。有关情绪与工作记忆相互作用的研究中,很多的证据表明,情绪对认知表现的影响可能是通过工作记忆完成的。本文对情绪分类,情绪影响工作记忆的相关理论及以往的相关研究进行了介绍,同时提出存在的问题并进行展望。     

Refractoriness and the healthy brain: A behavioural study on semantic access

While many behavioural studies on refractory phenomena in lexical/semantic access have focused on the mechanisms involved in the oral production of names, comprehension tasks have been almost exclusively used in neuropsychological studies on brain damaged patients. We report the results of two experiments on healthy participants conducted by means of speeded word to picture matching tasks. They assess the effects of the same variables examined in the study of refractory access dysphasic patients: semantic distance and word frequency (experiment 1) and presentation rate and serial position effects (experiment 2). Semantic access patients usually show little effect of word frequency but a large semantic distance effect. However, critical in characterising the syndrome as ‘refractory’, effects of presentation rate and serial position should also be present. The experiments involved the use of a deadline response procedure. The critical manipulation was the absence of a Response Stimulus Interval (RSI) in the fast presentation rate conditions; slower presentation rates involved 1 s RSI. With these manipulations the typical behavioural pattern of performance provided by semantic access dysphasic patients was reproduced. Semantic distance effects were more powerful than word frequency effects (experiment1). Presentation rate effects were found and, most important for a “refractory” account of the effects, a serial position effect was obtained (experiment 2). These results provide the first evidence of such a broad range of refractory effects at the same time in comprehension tasks in healthy subjects and support a purely semantic account for the locus of refractoriness. Moreover, error analysis showed a predominance of perseverative errors with subsequent representations of the same target, supporting a failure of cognitive control mechanisms as the cause of refractory behaviour. The findings are discussed in the light of current models of lexical and semantic processing.     

Developmental changes in infants’ visual short-term memory for location

To examine the development of visual short-term memory (VSTM) for location, we presented 6- to 12-month-old infants (N = 199) with two side-by-side stimulus streams. In each stream, arrays of colored circles continually appeared, disappeared, and reappeared. In the changing stream, the location of one or more items changed in each cycle; in the non-changing streams the locations did not change. Eight- and 12.5-month-old infants showed evidence of memory for multiple locations, whereas 6.5-month-old infants showed evidence of memory only for a single location, and only when that location was easily identified by salient landmarks. In the absence of such landmarks, 6.5-month-old infants showed evidence of memory for the overall configuration or shape. This developmental trajectory for spatial VSTM is similar to that previously observed for color VSTM. These results additionally show that infants’ ability to detect changes in location is dependent on their developing sensitivity to spatial reference frames.     

Memory deficits in Alzheimer's patients: A comprehensive review

Despite considerable experimental work on Alzheimer's disease (AD), the underlying cognitive mechanisms as well as the precise localization of neuropathological changes critical for memory loss remains undefined. A review of the neuropsychological literature on long-term memory deficits in AD patients suggests that AD patients display (a) a pervasive deficit of explicit memory, (b) a partial deficiency of implicit memory for verbal and visuoperceptual material (as measured by repetition priming procedures), and (c) a substantial sparing of implicit memory for visuomotor skills. The explicit memory loss is likely a result of encoding as well as consolidation difficulties. A faulty lexical-semantic knowledge structure appears responsible for deficient repetition priming effects. Since neuropathological changes diffusely affect the brain of AD patients, establishing a clear relationship between localization of cerebral lesions and memory deficits is particularly difficult. Nevertheless, data suggest that extensive involvement of the hippocampal-amygdala complex plays a major role in explicit memory loss. Damage to associative cortical areas likely is involved in repetition priming deficits. The relative integrity of primary motor and sensory cortical areas and of the basal ganglia likely subsume, by contrast, the normal learning of visuomotor skills.     

Coping with challenge and hindrance stressors in teams: Behavioral,cognitive, and affective outcomes

The purpose of this study was to utilize the challenge–hindrance framework to examine the discrete and combined effects of different environmental stressors on behavioral, cognitive, and affective outcomes at the team level. Results from 83 teams working on a command and control simulation indicated that the introduction of a challenge stressor positively affected team performance and transactive memory. The introduction of a hindrance stressor negatively affected team performance and transactive memory and positively affected psychological withdrawal. When the hindrance stressor was combined with the challenge stressor, teams exhibited the lowest levels of performance and transactive memory, and the highest levels of psychological withdrawal. These effects were due to the adoption of specific coping strategies by team members. Implications are discussed, as well as limitations and directions for future research.     

Overweight and cognition

There is a growing concern among health authorities that an increasing number of people in the Western world become overweight and even obese. It is well known that obesity is related to several diseases (e.g., diabetes, stroke, and high blood pressure) and that such diseases related to obesity lead to early death. It has also been discussed whether overweight and obesity in themselves or in relation to such diseases lead to cognitive decline. On the basis of data from a large, population‐based, prospective study we examined three cognitive domains: episodic memory, semantic memory, and spatial ability. Two body measures were used to define normal weight and overweight, body‐mass index and waist/hip ratio. Although these two body measures reveal quite different prevalence data of overweight, the associations between overweight and cognition are similar. For episodic memory, overweight interacts with age, but when controlling for hypertension, stroke and diabetes, this interaction disappears. For semantic memory, normal weight participants outperform overweight participants even after controlling for these diseases. For spatial ability, the well‐established advantage for men holds for young‐old and old‐old normal‐weight participants. For overweight participants, this advantage holds for middle‐age participants only. We conclude that there is a weight‐cognition relationship even after controlling for obesity‐related diseases. The results are discussed in terms of possible biological mechanisms.