The analysis of sex differences in cognitive abilities is largely confusing because these differences are masked by the pervasive influence of the general factor of intelligence (g). In this study a battery of five reasoning tests (abstract [AR], numerical [NR], verbal [VR], mechanical [MR], and spatial [SR]) was completed by a sample of 3233…

Sex differences on the Attention Test (AC), the Raven's Standard Progressive Matrices (SPM), and the Brazilian Cognitive Battery (BPR5), were investigated using four large samples (total N=6780), residing in the states of Minas Gerais and Sao Paulo. The majority of samples used, which were obtained from educational settings, could be considered a…

It has been proposed that males would show higher mean scores than females in general intelligence ("g") because (1) men have, on average, larger brains than women, and (2) brain volume correlates with "g." Here we report a failure to support the conclusion derived from these premises. High resolution MRIs were acquired in a sample of one hundred…

Here we apply a method for automated segmentation of the hippocampus in 3D high-resolution structural brain MRI scans. One hundred and four healthy young adults completed twenty one tasks measuring abstract, verbal, and spatial intelligence, along with working memory, executive control, attention, and processing speed. After permutation tests…

The authors argue that upon publication of a paper, the data should be made available through online archives or repositories. Reasons for not sharing data are discussed and contrasted with advantages of sharing, which include abiding by the scientific principle of openness, keeping the data for posterity, increasing one's impact, facilitation of…

In two experiments the neuronal mechanisms of sex differences in mental rotation were investigated. In Experiment 1 cortical activation was studied in women and men with similar levels of mental rotation ability (high, and average to low), who were equalized with respect to general intelligence. Sex difference in neuroelectric patterns of brain…

This register-based longitudinal study of 392 969 Norwegians examined associations between birth order, gender and educational attainment at age 25 years within families (fixed effects regression) and between families (ordinary OLS regression). Data were retrieved from national registers for births of mothers with single births only and a first…

A meta-analytic review investigated the association between general intelligence and interpersonal sensitivity. The review involved 38 independent samples with 2988 total participants. There was a highly significant small-to-medium effect for intelligence measures to be correlated with decoding accuracy (r=0.19, p less than 0.001). Significant…

Proton magnetic resonance spectroscopy ([to the first power]H-MRS) is a technique for the assay of brain neurochemistry "in vivo." N-acetylaspartate (NAA), the most prominent metabolite visible within the [to the first power]H-MRS spectrum, is found primarily within neurons. The current study was designed to further elucidate NAA-cognition…

Research into sex differences in general intelligence, g, has resulted in two opposite views. In the first view, a g-difference is nonexistent, while in the second view, g is associated with a male advantage. Past research using Multi-Group Covariance and Mean Structure Analysis (MG-CMSA) found no sex difference in g. This failure raised the…

Recently, different methodological approaches have been discussed as an explanation for inconsistencies in studies investigating sex differences in different intelligences. The present study investigates sex differences in manifest sum scores, factor score estimates, and latent verbal, numerical, figural intelligence, as well as fluid and…

Recent neuroimaging research has shown sex-related differences in the relationship between brain structure and cognitive function. Anatomical studies have shown a greater reliance for cognitive function on white matter structure in adult females, and a greater reliance on gray matter structure in adult males. Functional neuroimaging studies have…

This brief research note aims to estimate the magnitude of the association between general intelligence and physical attractiveness with large nationally representative samples from two nations. In the United Kingdom, attractive children are more intelligent by 12.4 IQ points (r=0.381), whereas in the United States, the correlation between…

Three prominent theories of intelligence, the Cattell-Horn-Carroll (CHC), extended fluid-crystallized (Gf-Gc) and verbal-perceptual-image rotation (VPR) theories, provide differing descriptions of the structure of intelligence (McGrew, 2009; Horn & Blankson, 2005; Johnson & Bouchard, 2005b). To compare these theories, models representing them were…

In three experiments, gender and ability (performance and emotional intelligence) related differences in brain activity--assessed with EEG methodology--while respondents were solving a spatial rotation tasks and identifying emotions in faces were investigated. The most robust gender related difference in brain activity was observed in the lower-2…