Extraversion,neuroticism, psychoticism and self-reported delinquency: Evidence from eight separate samples

Eight separate samples of high school and university students (Total N = 410) in Britain and Canada were used to test predictions from Eysenck's theory that delinquents should be high scorers on scales of extraversion, neuroticism, and psychoticism. Self-report paper- and pencil-questionnaire measures of both personality and delinquency were administered under conditions that ensured anonymity. The evidence showed clear support for a relationship between high delinquency scores and high scores on both extraversion and psychoticism. These relationships held up across diverse samples and different ways of analyzing the data. No support was found for a relationship between delinquency scores and the dimension of neuroticism.     

Hypothalamo-Pituitary-Adrenocortical Regulation Following Lesions of the Central Nucleus of the Amygdala

Previous reports indicate that the central nucleus of the amygdala (CeA) stimulates adrenocorticotropin and corticosterone secretion, suggesting a role for this region in central hypothalamo-pituitary-adrenocortical (HPA) stress regulation. To evaluate this hypothesis, this study assessed the impact of CeA lesion on the response of hypophysiotrophic paraventricular nucleus (PVN) neurons to acute restraint and chronic unpredictable stress exposure. In contrast to previous reports, CeA lesions did not affect corticosterone or ACTH secretion induced by acute stress. Acute restraint increased PVN corticotropin releasing hormone (CRH) mRNA expression, increased the number of parvocellular PVN neurons expressing the co-secretagogue arginine vasopressin (AVP), and induced cFOS mRNA expression in the parvocellular PVN. However, there was no additional effect of CeA lesion on any measure of PVN activation. Chronic unpredictable stress exposure induced long-term activation of the HPA axis, noted by thymic involution, adrenal hypertrophy and increased PVN CRH mRNA expression. Stress-induced changes in thymus and adrenal weights were not affected by CeA lesion. Further, CeA lesion rats did not differ from controls in post-stress CRH mRNA expression. However, basal CRH mRNA expression was increased in the PVN of CeA rats, suggesting that the CeA plays a role in long-term inhibition of the PVN. The results of these studies are not consistent with the hypothesis that the CeA is necessary for stress-induced pituitary-adrenocortical activation. Rather, this region may play a stressor-specific modulatory role in regulation of HPA function.     

Black–White differences on the g-factor in South Africa: a “Jensen Effect” on the Wechsler Intelligence Scale for Children — revised

A test is made to determine whether South African Black–White differences on various tests of cognitive performance are like the Black–White differences in the United States in being positively associated with a test's g loadings, where g is the general factor of intelligence. Data are analyzed from Skuy, Schutte, Fridjhon and O'Carroll [Skuy, M., Schutte, E., Fridjhon, P., & O'Carroll, S. (2001). Suitability of published neuropsychological test norms for urban African secondary school strudents in South Africa. Personality and Individual Differences, 30, 1413–1425) of 154 13- to 15-year-old secondary school students in Soweto, Johannesburg, on the Wechsler Intelligence Scale for Children–Revised (WISC-R). The more highly correlated a sub-test was with g, the more it predicted the African–White difference (r =0.77, p=0.05). The effect remained even when the Vocabulary sub-test was excluded or when g was extracted from the Black rather than from the White standardization sample (r=0.60, P<0.05), as it did as well if Spearman's rho was used instead of Pearson's r (g from Whites=0.74, g from Blacks=0.74, P< 0.005). Understanding observed Black–White differences around the world requires new research on the nature and nurture of g.     

Surface dependent segregation of Y2O3 in t-ZrO2

Atomistic simulation techniques have been used to predict the preferential segregation of Y³⁺ ions to the (100), (101) and (110) surfaces of tetragonal zirconia (t-ZrO₂). It is found that segregation energetics vary greatly between surfaces. In particular, dopant ions segregate to the top of the (101) surface. Conversely, although they also segregate towards the (100) and (110) surfaces, Y³⁺ becomes trapped just beneath these surfaces. For all of these surfaces, segregation effects are negligible below 12Å. The surface orientation dependence will result in significant variations in the concentration of yttrium at different surfaces. As a consequence, properties that are a function of defect concentration and distribution will be surface dependent. Predictive understanding of such segregation effects will provide the possibility of better engineered devices for a variety of thermal and electrochemical applications.     

The evolutionary selection of human races: A response to Miller

Miller's (1993, Personality and Individual Differences, 15, 665–675) theory of the origin of “the African Personality” is not new. The focus on testosterone as a mediator of male-male agonistic interaction and strong sexuality has been a component of the r-K analysis of human race differences from the outset. Several aspects of Miller's paper are discussed.     

Relation between aging and rated teaching effectiveness of academic psychologists

Within a combined cross-sectional and longitudinal design, several analyses showed that student-rated teaching effectiveness in university professors declined with age. For 106 full-time psychology teachers, aged 26 to 55, who were studied for time periods ranging from 2 to 15 years, an overall negative correlation of r = -.33 (p less than .05) was found between age and general teaching effectiveness. A similar decrement with age occurred for items measuring specific teaching behaviors. Age accounted for 8% of the variance in general teaching effectiveness.