Longitudinal Changes in Memory Performance and Processing Speed in Old Age abstract Keywords

The speed theory of cognitive aging posits that an age-related slowing of processing speed leads to impairments in higher order cognitive functions, such as memory. However, only few studies have examined the relationship between longitudinal changes in processing speed and longitudinal changes in memory performance. In the present study, data of 474 older adults (T1: 59–65 years) from the Interdisciplinary Longitudinal Study on Adult Development (ILSE) were used to investigate whether changes in speed and in memory were associated over a 4-year period. Performance changes in both constructs were analyzed using latent change factor models. Results show that latent changes in processing speed and latent changes in memory performance correlated with 0.61. This association is considerably lower than what would have been expected from cross-sectional data. Our longitudinal results suggest that although speed changes explain a substantial proportion of variance in memory changes, additional explanatory factors must be taken into consideration.     

Development of Community Psychology

The growth and development of community psychology in Zambia has been necessitated by many social problems encountered by Zambians be they health, economic or psychological. The work of governmental and nongovernmental organizations at community level has contributed to the development of this sub-field of psychology. Community psychology in Zambia has many challenges to overcome, including the lack of trained manpower and availability of funds. Community psychology has great potential to contribute to the wellbeing of different communities in Zambia.     

Factor structure of the construct of adaptive behavior in children with and without intellectual disability

Although the presence of significant limitations in adaptive behavior constitutes one of the three necessary criteria for diagnosing intellectual disability, adaptive behavior structure has always been the subject of considerable controversy among researchers. The main goal of this study is to extend previous research results that provide further support to a multidimensional structure of conceptual, social, and practical skills compared to the unidimensional structure. One-factor and 3-correlated factors models as measured by 15 observable indicators were analyzed by means of confirmatory factor analysis (CFA), as well as their relationships with one second-order factor (i.e., adaptive behavior). To that end, 388 children with and without intellectual disabilities were assessed with the Diagnostic Adaptive Behavior Scale (DABS). Results of CFA indicated that the 3 first-order factors solution provides the best fit to the data. Reliability and validity of the multidimensional model were also analyzed through different methods such as the composite reliability and the average variance extracted. Finally, implications of these findings and possible directions for future research are discussed.     

The bidirectional relation between positive mental health and psychopathology in a longitudinal representative panel study

Background: There is accumulating evidence that positive mental health and psychopathology should be seen as separate indicators of mental health. This study contributes to this evidence by investigating the bidirectional relation between positive mental health and psychopathological symptoms over time. Methods: Positive mental health (MHC-SF) and psychopathological symptoms (BSI) were longitudinally measured in a representative adult sample (N?=?1932) on four measurement occasions in nine months. A cross-lagged panel design was applied and evaluated with a latent growth model combined with an item response theory measurement model. Results: Psychopathological symptoms were longitudinally related to positive mental health and vice versa, controlling for initial levels. The changes over time were even more important than the absolute levels of psychopathological symptoms and positive mental health, respectively. Conclusions: The results underline the need for a comprehensive perspective on mental health, incorporating both the treatment of symptoms and the enhancement of well-being.     

A study of Mind Image Drawings

This report dealt with a newly introduced method of drawing named, “Mind Image Drawings.” First, the subjects depicted images in their mind freely. Second, the subjects described their own pictures using three epithets. Third, the subjects added “I am” to these words, and read them aloud. Through these techniques, the subjects not only projected the unconscious side of their mind in the drawings, but also could obtain insight into their mind on the cognitive level. Last, the subjects judged their drawings using 17 semantic differential scales. The “originality factor,” the “evaluation factor,” and several types of “expressiveness factors” were extracted in the factor analyses of the scales.     

Heterogeneous factor analysis models: A bayesian approach

Multilevel factor analysis models are widely used in the social sciences to account for heterogeneity in mean structures. In this paper we extend previous work on multilevel models to account for general forms of heterogeneity in confirmatory factor analysis models. We specify various models of mean and covariance heterogeneity in confirmatory factor analysis and develop Markov Chain Monte Carlo (MCMC) procedures to perform Bayesian inference, model checking, and model comparison.We test our methodology using synthetic data and data from a consumption emotion study. The results from synthetic data show that our Bayesian model perform well in recovering the true parameters and selecting the appropriate model. More importantly, the results clearly illustrate the consequences of ignoring heterogeneity. Specifically, we find that ignoring heterogeneity can lead to sign reversals of the factor covariances, inflation of factor variances and underappreciation of uncertainty in parameter estimates. The results from the emotion study show that subjects vary both in means and covariances. Thus traditional psychometric methods cannot fully capture the heterogeneity in our data.     

Agonistic behavior and growth in newly emerged brown trout (Salmo trutta L) of sea‐ranched and wild origin

Selection experiments and game theory models have revealed that the changes in agonistic behavior following selection for rapid growth rate of fish depend on the access of food. If food is spatially restricted and in excess of demand, the intensity of agonistic behaviors will decrease. This prediction was tested in an experiment on wild and sea‐ranched brown trout (Salmo trutta L.) fry originating from a common stock. Agonistic behavior, activity, and specific growth rate were studied in tanks (56 × 56 cm) at high (159.4 fry/m²) and low (9.6 fry/m²) stocking densities given either a large or small food ration (3.0% and 1.5%, respectively, food per total body weight and day). Observations were done during 4 days in each trial. Generally, fry of sea‐ranched origin had a higher growth rate. No differences in activity were found. Intensity of agonistic behavior was higher among wild groups. There was a tendency for interaction between density and strain, e.g., wild fish were relatively more aggressive at higher densities. Food ration had no effect on level of agonistic behavior. These results indicate that the selection for rapid growth in hatcheries may indirectly select for reduced aggressiveness. Genetic integrity and diversity of wild populations may be threatened when interbreeding occurs between wild and hatchery fish. Aggr. Behav. 28:145–153, 2002. © 2002 Wiley‐Liss, Inc.     

Confirming the Factor Structure of Attention Deficit Hyperactivity Disorder Symptoms in Adult, Nonclinical Samples

Three separate models have been proposed to describe the factor structure of attention deficit hyperactivity disorder (ADHD) in the past 20 years. The Diagnostic and Statistical Manual of Mental Disorders-III (DSM-III, 1980) proposed 3 separate factors of inattention, hyperactivity, and impulsivity. The DSM-III-R (1987) proposed a single factor. The DSM-IV (1994) described the disorder as having 2 factors: hyperactivity/impulsivity and inattention. The following 2 studies employed confirmatory factor analysis to compare each of these models and 3 alternative models. University students completed questionnaires that assessed each of the 18 symptoms listed in the DSM-IV for ADHD. The 3-factor model fit the data significantly better than each of the other models in both studies. These findings suggest that a 3-factor model of inattention, hyperactivity, and impulsivity describes adult ADHD symptoms better than current alternatives.     

A Latent Variable Framework for Power Estimation Within Intervention Contexts

This paper presents a latent growth SEM approach for the estimation of treatment effects, and power to detect such effects, within a true experimental design setting in which subjects are randomly assigned to treatment and control conditions. Power estimation is a critical component of intervention experiment design and the testing of their results. Although researchers have become increasingly sophisticated in applying tests for statistical significance in intervention contexts, few are aware of the power of these tests. The issues raised in this paper are not new; however, reminding researchers to consider these points is important. Exactly how the researcher handles these issues will depend on the questions asked and the resources available, as well as other considerations. Discussion underscores the relationship between the reliability of a study's measures and concomitant increases in power obtained within the SEM framework.     

基于概念复杂度的加工容量观

探讨了一个认知科学的概念——容量,主要是介绍一种基于概念维度的加工容量观.这种观点认为加工容量最好以进入某一特定运算过程的独立维度来定义,容量的增长意味着可以表征更多的维度,而概念的组块与分割是常用的表征策略.个体差异通过表征的清晰度和有效性的差异来表现,而认知的发展则是成熟与经验相互作用的结果.