Tests of fluid intelligence predict success in a wide range of cognitive activities. Much uncertainty has surrounded brain lesions producing deficits in these tests, with standard group comparisons delivering no clear result. Based on findings from functional imaging, we propose that the uncertainty of lesion data may arise from the specificity and complexity of the relevant neural circuit. Flu...

Global composites (e.g., IQs) calculated in intelligence tests are interpreted as indexes of the general factor of intelligence, or psychometric g. It is therefore important to understand the proportion of variance in those global composites that is explained by g. In this study, we calculated this value, referred to as hierarchical omega, using large-scale, nationally representative norming sa...

Background: Congenital hypothyroidism (CH) is one of the preventable causes of intellectual disability. The aim of this study was to compare intelligence quotient (IQ) in early treated children with CH and healthy children. Materials and Methods: This cohort study was conducted on 78 early tre...

This article examines the role of the BIG 5 and general mental ability (GMA) for the prediction of current achievement motivation (CAM) in an ability testing context. A total of 189 participants took two figural matrices tests, and 90 of them received a training intervention between tests. Separate analyses for both tests showed openness, conscientiousness, and neuroticism to significantly pred...