APP23 mice as a model of Alzheimer's disease: an example of a transgenic approach to modeling a CNS disorder

Animal models are considered essential in research ensuing elucidation of human disease processes and subsequently, testing of potential therapeutic strategies. This is especially true for neurodegenerative disorders, in which the first steps in pathogenesis are often not accessible in human patients. Alzheimer's disease is vastly becoming a major medical and socioeconomic problem in our aging society. Valid animal models for this uniquely human condition should exhibit histopathological, biochemical, cognitive, and behavioral alterations observed in Alzheimer's disease patients. Major progress has been made since the understanding of the genetic basis of Alzheimer's disease and the development and improvement of transgenic mouse models. All present Alzheimer's disease models developed are partial but nevertheless essential in further unraveling the nature and spatial and temporal development of the complex molecular pathology underlying this condition. One of the more recent transgenic attempts to model Alzheimer's disease is the APP23 transgenic mouse. This article describes the development and assessment of this human amyloid precursor protein overexpression model. We summarize histopathological and biochemical, cognitive and behavioral observations made in heterozygous APP23 mice, thereby emphasizing the model's contribution to clarification of neurodegenerative disease mechanisms. In addition, the first therapeutic interventions in the APP23 model are included.     

Reactions to Recruitment Web Sites: Visual and Verbal Attention, Attraction, and Intentions to Pursue Employment

Purpose

We investigate job seeker visual and verbal attention, and perceptions regarding company web sites in the applicant generation phase of recruitment.

Design/Methodology/Approach

We report three studies using varied methodological approaches including eye-tracking, verbal protocol analysis (VPA), and survey data.

Findings

Eye-tracking results suggest Web-based job seekers focus visual attention on information containing hyperlinks and on text more than graphic images or navigation tools. VPA suggests Web-based job seekers focus verbal attention on content more than design, especially job opening information. Survey results suggest content, design, and communication features are all related to applicant attraction. Design explains the most incremental variance in web site evaluation, while perceptions of communication features explain the most incremental variance in attitude toward the organization and intentions to pursue employment.

Implications

We provide multi-method evidence concerning features that attract applicant visual and verbal attention, and influence attraction and intentions to pursue employment. The findings also provide practical implications for designing recruitment web sites.

Originality/Value

We report three methodologically distinct perspectives on an important and timely issue: Web-based recruitment. We are aware of no other psychomotor eye-tracking studies in the recruitment literature, and only one other VPA. Combining multiple methods in this way provides unique perspective.     

SCA with rotation to distinguish common and distinctive information in linked data

Often data are collected that consist of different blocks that all contain information about the same entities (e.g., items, persons, or situations). In order to unveil both information that is common to all data blocks and information that is distinctive for one or a few of them, an integrated analysis of the whole of all data blocks may be most useful. Interesting classes of methods for such an approach are simultaneous-component and multigroup factor analysis methods. These methods yield dimensions underlying the data at hand. Unfortunately, however, in the results from such analyses, common and distinctive types of information are mixed up. This article proposes a novel method to disentangle the two kinds of information, by making use of the rotational freedom of component and factor models. We illustrate this method with data from a cross-cultural study of emotions.     

Does category labeling lead to forgetting?

What effect does labeling an object as a member of a familiar category have on memory for that object? Recent studies suggest that recognition memory can be negatively impacted by categorizing objects during encoding. This paper examines the “representational shift hypothesis” which argues that categorizing an object impairs recognition memory by altering the trace of the encoded memory to be more similar to the category prototype. Previous evidence for this idea comes from experiments in which a basic-level category labeling task was compared to a non-category labeling incidental encoding task, usually a preference judgment (e.g., “Do you like this item?”). In two experiments, we examine alternative tasks that attempt to control for processing demands and the degree to which category information is explicitly recruited at the time of study. Contrary to the predictions of the representational shift hypothesis, we find no evidence that memory is selectively impaired by category labeling. Overall, the pattern of results across both studies appears consistent with well-established variables known to influence memory such as encoding specificity and distinctiveness effects.     

Speaking two languages with different number naming systems: What implications for magnitude judgments in bilinguals at different stages of language acquisition?

Differences between languages in terms of number naming systems may lead to performance differences in number processing. The current study focused on differences concerning the order of decades and units in two-digit number words (i.e., unit-decade order in German but decade-unit order in French) and how they affect number magnitude judgments. Participants performed basic numerical tasks, namely two-digit number magnitude judgments, and we used the compatibility effect (Nuerk et al. in Cognition 82(1):B25–B33, 2001) as a hallmark of language influence on numbers. In the first part we aimed to understand the influence of language on compatibility effects in adults coming from German or French monolingual and German–French bilingual groups (Experiment 1). The second part examined how this language influence develops at different stages of language acquisition in individuals with increasing bilingual proficiency (Experiment 2). Language systematically influenced magnitude judgments such that: (a) The spoken language(s) modulated magnitude judgments presented as Arabic digits, and (b) bilinguals’ progressive language mastery impacted magnitude judgments presented as number words. Taken together, the current results suggest that the order of decades and units in verbal numbers may qualitatively influence magnitude judgments in bilinguals and monolinguals, providing new insights into how number processing can be influenced by language(s).     

Reduction of left visual field lexical decision accuracy as a result of concurrent nonverbal auditory stimulation

To investigate whether concurrent nonverbal sound sequences would affect visual-hemifield lexical processing, lexical-decision performance of 24 strongly right-handed students (12 men, 12 women) was measured in three conditions: baseline, concurrent neutral sound sequence, and concurrent emotional sound sequence. With the neutral sequence, Naveteru, Roy, Ovelac, and Steinling (1992) had observed a right greater than left cerebral blood flow, and an opposite pattern with the emotional sequence. In the present study, the neutral sound sequence induced a significant accuracy reduction for lexical decisions to stimuli presented in the left visual field. It is hypothesized that RH activation in response to neutral sounds interferes with the limited lexical processing resources of that hemisphere.     

Reasons and Promotion

A number of philosophers accept promotionalism, the view that whether there is a normative reason for an agent to perform an action or have an attitude depends on whether her doing so promotes a value, desire, interest, goal, or end. I show that promotionalism faces a prima facie problem when it comes to reasons for belief: it looks extensionally inadequate. I then articulate two general strategies promotionalists can (and have) used to solve this problem and argue that, even if one of these two strategies can successfully solve the problem with reasons for belief, promotionalists face a symmetrical problem in a range of structurally similar cases. As I'll argue, the problem is that promotionalism cannot account for reasons grounded in the ‘fit’ between an attitude and its object. I offer an alternative to promotionalism and explain how adopting this alternative solves the problems with promotionalism while preserving much of what made promotionalism attractive in the first place.