Efficacy of caffeine versus expectancy in altering caffeine-related symptoms

The study investigated the independent and interactive effects of caffeine and expectancy on caffeine-related symptoms. High- and low-caffeine consumers were randomly assigned to either an expectancy or nonexpectancy instructional set and one of four caffeine doses. Subjects were administered the State-Trait Anxiety Inventory, (Spielberger & Gorsuch, 1970) and a Symptom Questionnaire (Christensen, White, Krietsch, & Steele, 1990) prior to and 45 min following consumption of one of the four caffeine doses. An analysis of covariance identified a significant main effect for the State-Trait Anxiety Inventory scores and significant main and interaction effects for four Symptom Questionnaire items. However, when the alpha levels were corrected for the increased probability of Type I error, using the Bonferroni procedure, these effects failed to achieve significance. These results suggest that previous reports of subjective caffeine effects are also suspect because of their failure to control for the increased probability of Type I error.     

A Psychometric Network Perspective on the Validity and Validation of Personality Trait Questionnaires

This article reviews the causal implications of latent variable and psychometric network models for the validation of personality trait questionnaires. These models imply different data generating mechanisms that have important consequences for the validity and validation of questionnaires. From this review, we formalize a framework for assessing the evidence for the validity of questionnaires from the psychometric network perspective. We focus specifically on the structural phase of validation, where items are assessed for redundancy, dimensionality, and internal structure. In this discussion, we underline the importance of identifying unique personality components (i.e. an item or set of items that share a unique common cause) and representing the breadth of each trait's domain in personality networks. After, we argue that psychometric network models have measures that are statistically equivalent to factor models but we suggest that their substantive interpretations differ. Finally, we provide a novel measure of structural consistency, which provides complementary information to internal consistency measures. We close with future directions for how external validation can be executed using psychometric network models. © 2020 European Association of Personality Psychology     

Three questions about Leplin’s reliabilism

Jarrett Leplin’s paper is multifaceted; it’s rich with ideas, and I won’t even try to touch on all of them. Instead, I’d like to raise three questions about the paper: one about its definition of reliable method, one about its solution to the generality problem, and one about its answer to clairvoyance-type objections.     

The affect heuristic and the attractiveness of simple gambles

Prior studies have observed that the attractiveness of playing a simple gamble (7/36 to win $9; otherwise win nothing) is greatly enhanced by introducing a small loss (7/36 win $9; otherwise lose 5¢). The present studies tested and confirmed an explanation of this finding based on the concept of evaluability and the affect heuristic. Evaluators of the “no‐loss” gamble lack a precise feeling for how good $9 is, hence give it little weight in their judgment. In the second gamble, comparison with the small loss makes $9 “come alive with feeling” and become weighted in the judgment, thus increasing the attractiveness of the gamble. These results demonstrate the importance of contextual factors in determining affect and preference for simple risk‐taking opportunities. They show that the meaning, utility, and weighting of even a very familiar monetary outcome such as $9 is not fixed, but depends greatly on these contextual factors. Copyright © 2007 John Wiley & Sons, Ltd.     

Alzheimer's disease: progress in the development of anti-amyloid disease-modifying therapies

The amyloid hypothesis--the leading mechanistic theory of Alzheimer's disease--states that an imbalance in production or clearance of amyloid beta (Abeta) results in accumulation of Abeta and triggers a cascade of events leading to neurodegeneration and dementia. The number of persons with Alzheimer's disease is expected to triple by mid-century. If steps are not taken to delay the onset or slow the progression of Alzheimer's disease, the economic and personal tolls will be immense. Different classes of potentially disease-modifying treatments that interrupt early pathological events (ie, decreasing production or aggregation of Abeta or increasing its clearance) and potentially prevent downstream events are in phase II or III clinical studies. These include immunotherapies; secretase inhibitors; selective Abeta42-lowering agents; statins; anti-Abeta aggregation agents; peroxisome proliferator-activated receptor-gamma agonists; and others. Safety and serious adverse events have been a concern with immunotherapy and gamma-secretase inhibitors, though both continue in clinical trials. Anti-amyloid disease-modifying drugs that seem promising and have reached phase III clinical trials include those that selectively target Abeta42 production (eg, tarenflurbil), enhance the activity of alpha-secretase (eg, statins), and block Abeta aggregation (eg, transiposate).     

Mindreading as social expertise

In recent years, a number of approaches to social cognition research have emerged that highlight the importance of embodied interaction for social cognition (Reddy, How infants know minds, 2008; Gallagher, J Conscious Stud 8:83–108, 2001; Fuchs and Jaegher, Phenom Cogn Sci 8:465–486, 2009; Hutto, in Seemans (ed.) Joint attention: new developments in psychology, philosophy of mind and social neuroscience, 2012). Proponents of such ‘interactionist’ approaches emphasize the importance of embodied responses that are engaged in online social interaction, and which, according to interactionists, present an alternative to mindreading as a source of social understanding. We agree that it is important to take embodied interaction seriously, but do not agree that this presents a fundamental challenge to mainstream mindreading approaches. Drawing upon an analogy between embodied interaction and the exercise of expert skills, we advocate a hierarchical view which claims that embodied social responses generally operate in close conjunction with higher-level cognitive processes that play a coordinative role, and which are often sensitive to mental states. Thus, investigation of embodied responses should inform rather than conflict with research on mindreading.     

Analyses of Model Fit and Robustness. A New Look at the PISA Scaling Model Underlying Ranking of Countries According to Reading Literacy

This paper addresses methodological issues that concern the scaling model used in the international comparison of student attainment in the Programme for International Student Attainment (PISA), specifically with reference to whether PISA’s ranking of countries is confounded by model misfit and differential item functioning (DIF). To determine this, we reanalyzed the publicly accessible data on reading skills from the 2006 PISA survey. We also examined whether the ranking of countries is robust in relation to the errors of the scaling model. This was done by studying invariance across subscales, and by comparing ranks based on the scaling model and ranks based on models where some of the flaws of PISA’s scaling model are taken into account. Our analyses provide strong evidence of misfit of the PISA scaling model and very strong evidence of DIF. These findings do not support the claims that the country rankings reported by PISA are robust.