Spatial Working Memory in Aging and Mild Cognitive Impairment: Effects of Task Load and Contextual Cueing

ABSTRACT

Mild Cognitive Impairment (MCI) is characterized by episodic memory deficits, while aspects of working memory may also be implicated, but studies into this latter domain are scarce and results are inconclusive. Using a computerized search paradigm, this study compares 25 young adults, 25 typically aging older adults and 15 amnestic MCI patients as to their working-memory capacities for object-location information and potential differential effects of memory load and additional context cues. An age-related deficit in visuospatial working-memory maintenance was found that became more pronounced with increasing task demands. The MCI group additionally showed reduced maintenance of bound information, i.e., object-location associations, again especially at elevated memory load. No effects of contextual cueing were found. The current findings indicate that working memory should be considered when screening patients for suspected MCI and monitoring its progression.     

Performance on a measure of category fluency in cognitively impaired elderly

ABSTRACT

Measures of verbal fluency are widely used in the assessment of cognitive functioning of the elderly. However, limited research has evaluated patterns (across specific timed intervals) of performance on tasks of language fluency in different forms of dementia. The current study investigated semantic fluency in 488 elderly individuals (249 with Alzheimer's dementia, 97 Vascular dementia, 97 Mild Cognitive Impairment and 45 cognitively intact) across 15-second intervals in an animal naming task using retrospective chart review. Normal controls produced significantly more exemplars and AD patients produced fewer animal names than the other groups. After the first 15- second time interval, the demented groups produced significantly fewer exemplars than the non-demented. At the end of 30 seconds it was possible to differentiate normal aging from MCI who no longer differed from the VaD group. Overall, it appears that the greatest and most clinically meaningful differences between the diagnostic groups were detected in the first three 15-second intervals. The present findings support the use of time intervals and total scores on tasks of verbal fluency in clinical settings and for research purposes.     

Differential Memory Test Sensitivity for Diagnosing Amnestic Mild Cognitive Impairment and Predicting Conversion to Alzheimer's Disease

ABSTRACT

Episodic memory is the first and most severely affected cognitive domain in Alzheimer's disease (AD), and it is also the key early marker in prodromal stages including amnestic mild cognitive impairment (MCI). The relative ability of memory tests to discriminate between MCI and normal aging has not been well characterized. We compared the classification value of widely used verbal memory tests in distinguishing healthy older adults (n = 51) from those with MCI (n = 38). Univariate logistic regression indicated that the total learning score from the California Verbal Learning Test-II (CVLT-II) ranked highest in terms of distinguishing MCI from normal aging (sensitivity = 90.2; specificity = 84.2). Inclusion of the delayed recall condition of a story memory task (i.e., WMS-III Logical Memory, Story A) enhanced the overall accuracy of classification (sensitivity = 92.2; specificity = 94.7). Combining Logical Memory recognition and CVLT-II long delay best predicted progression from MCI to AD over a 4-year period (accurate classification = 87.5%). Learning across multiple trials may provide the most sensitive index for initial diagnosis of MCI, but inclusion of additional variables may enhance overall accuracy and may represent the optimal strategy for identifying individuals most likely to progress to dementia.     

The usefulness of the story recall test in patients with mild cognitive impairment and Alzheimer's disease

ABSTRACT

Background: The story recall test (SRT) is one of the most reliable neuropsychological assessments for evaluating verbal memory function in order to distinguish between individuals with normal aging, mild cognitive impairment (MCI), and Alzheimer's disease (AD). The SRT is analogous to the logical memory test in Wechsler Memory Scale-III, which has recently been developed and standardized to apply to older adults in Korea. The purpose of this study was to examine the usefulness of the SRT and its ability to discriminate between normal cognitive aging and patients with MCI or AD. Methods: One hundred and twelve patients with MCI, 97 patients with AD, and 53 healthy elderly adults participated in this study. The SRT was compared with the Clinical Dementia Rating (CDR), Global Deterioration Scale (GDS), Korean version of the Mini Mental State Examination (K-MMSE), and the Korean version of the Hopkins Verbal Learning Test (K-HVLT). Results: The SRT was well-correlated with the dementia rating scales and the K-HVLT. However, the sensitivity and specificity of the SRT was greatly influenced by the level of education of the subjects. Conclusions: The SRT is a sensitive measurement of verbal memory function that can be used in clinical settings to discriminate between normal memory functioning and the very early and moderate stages of AD in a Korean population. Moreover, it is important to recognize that the SRT is more appropriate for subjects with a high level of education rather than a low level of education to differentiate normal cognitive aging from MCI or AD.     

学习风格与中美大学生课堂学习行为的关系研究

中美学生存在课堂学习行为差异的现象得到了中外众多教育工作者的关注和讨论.本文作者推测,中美学生在学习风格上存在的结构取向和深度取向的差异,是导致他们表现出不同课堂行为反应的一个原因.本研究采用学习风格量表和课堂学习行为量表对281名中国大学生和206名美国大学生施测.数据分析结果表明,中美学生存在学习风格与课堂学习行为的显著差异;学习风格的结构取向与课堂学习行为呈显著负相关,深度取向与课堂学习行为呈显著正相关;结构取向的学习风格在文化组别与课堂学习行为之间存在部分中介作用,表明结构取向至少能部分地解释中美大学生之间的课堂学习行为差异.     

The Effects of Instructor Fear Appeals and Moral Appeals on Cheating-Related Attitudes and Behavior of University Students

Little attention has been paid in academic dishonesty literature to empirically testing the effectiveness of different instructor communication strategies to minimize cheating. Using a quasi-experimental design, we compared the effectiveness of instructor fear appeals and moral appeals on student cheating-related attitudes and behavior. Cheating was most strongly associated with neutralizing attitudes in the moral appeal condition. Also, the relationship between observation of others cheating and self-reported cheating behaviors was stronger in both treatment conditions than in the control condition. Although a trend toward less cheating in the treatment conditions was evident, it did not attain statistical significance.     

Erratum

Abstract

Recent research has highlighted the central role of disgust in the etiology and maintenance of contamination aversion (CA). Data would also suggest that, although amendable to the treatment of choice for CA (exposure and response prevention [ERP]), disgust is resistant to habituation. However, with regard to CA, it is not yet known if disgust's resistance to habituation is an artifact of the emotion or the disorder. Specifically, research has not yet indicated if severity of CA moderates the effect of ERP on disgust. Utilizing an undergraduate convenience sample (n=33), the present study compared emotional responding (disgust and fear) with repeated exposure to a disgusting contamination-relevant stimulus between participants who are high in contamination aversion (HCA; n=17) and low in contamination aversion (LCA; n=16). Results indicated that, habituation of disgust was slower than fear within the HCA group but not the LCA group. Contrasts revealed that the decay of fear across trials was faster for HCA participants when compared with LCA participants, although decay of disgust was similar between groups. These results indicate that habituation of disgust is slower than fear when elevated CA is present.     

Worry: A critical analysis of some theoretical approaches

Abstract

It is suggested that worry has not been given serious academic attention due to problems of definition, and a prevailing belief that it is an unnecessary addition to the theorists vocabulary given the term “anxiety”. However, an increasing awareness of the importance of cognitive factors in emotional disorders makes the study of worry a necessary endeavour. Furthermore, inclusion of worry in DSM III-R as the principle diagnostic index of Generalised Anxiety Disorder has given the term clinical credibility. Three theoretical approaches to the subject of worry are considered: the test anxiety literature, which has focused on the effects of worry on performance, and two largely clinical accounts, a tripartite theory of worry and anxiety proposed by Borkovec, Metzger, and Pruzinsky (1986), and the model of anxious apprehension proposed by Barlow (1988). All approaches are critically evaluated, and suggestions made for future formulations.     

Experiences of stereotyping among individuals employed in selected South African organisations

This study investigated the effects of stereotypes among individuals working in selected South African organisations. The participants were 336 employees within the following sectors: banking (n?=?40), higher education institutions (n?=?72), mining (n?=?63), municipalities (n?=?24), nursing (n?=?4), police services (n?=?20), schools (n?=?85), and the restaurant industry (n?=?28). Data were collected using open ended interviews, and thematically analysed. The findings indicated that stereotypes influence individuals on three different levels: cognitive, behavioural, and emotional levels. Predominantly, participants reported that they mostly react in a cognitive manner when confronted with stereotypes.     

Nicotine exposure effects on ADHD in young adults with Attention Deficit Hyperactive Disorder (ADHD)

This study investigated whether ingestion of nicotine could enhance cognitive performance in people with ADHD. Participants with ADHD (n = 17) and without ADHD (n = 22) were contrasted for nicotine use. Cognitive performance was measured using selected subtests of the Cambridge Neuropsychological Test Automated Battery (CANTAB). Baseline cognitive performance data were collected prior to experimental nicotine exposure. The ADHD group with nicotine exposure performed significantly better than the non-exposure group post-intervention. Nicotine exposure appears to boost cognitive performance in subjects with ADHD.