Influence of Socio-Demographic Factors on SRAVEN Performance

This exploratory study aimed to investigate the influence of specific socio-demographic variables on a computerized test of non-verbal neuropsychological performance. Six hundred and thirty South African first year students were assessed using the University of Pennsylvania Computerized Neuropsychological Test Battery (PennCNP). Fluid intelligence was measured by a computerized version of the Raven's Progressive Matrices (SRAVENS). Analysis of variance indicated that gender, home language, quality of schooling, language of schooling and paternal education influenced performance on the SRAVEN. Stepwise multiple regression evidenced the importance of language, paternal education and high school language on SRAVENS responses. The assumption of non-verbal test scores as being independent of socio-demographic factors needs to be revisited as such independence cannot be maintained in light of such evidence.     

Rumination and Impaired Cortisol Recovery Following a Social Stressor in Adolescent Depression

Response styles theory promotes rumination as a central cognitive construct driving negative mood and depression, and past research suggests that at least part of the mechanism driving rumination’s depressogenic effect is through inhibiting the individual’s ability to shift attentional focus away from negative environmental stimuli. In the current study, we hypothesized that high trait rumination would be associated with impaired recovery of the body’s biological response to psychological stress. In a community sample of depressed (n?=?31) and non-depressed (n?=?33) adolescents we assessed rumination and the more adaptive trait of distraction and problem-solving with the Children’s Response Styles Questionnaire (CRSQ; Abela 2000), and diagnostic status was confirmed using the Child and Adolescent Schedule of Affective Disorders and Schizophrenia (K-SADS; Kaufman et al. Journal of the American Academy of Child and Adolescent Psychiatry 36:980–988, 1997). Participants completed the Trier Social Stress Test (TSST; Kirschbaum et al. Neuropsychobiology 28:76–81, 1993), and the focus of our analyses was the change in salivary cortisol concentration between peak cortisol output (25 min post-stressor) and a sample taken during the “Recovery” period 65 minutes post-stressor. Consistent with the predictions of response style theory, among the depressed adolescents only, high trait rumination was associated with delayed post-stressor cortisol recovery, whereas high trait distraction and problem-solving was associated with more rapid recovery. In contrast, response styles were not associated with cortisol recovery in the non-depressed group. These findings implicate impaired post-stress cortisol recovery as a potential mechanism underlying the pathological effect of rumination on the development and maintenance of Major Depressive Disorder (MDD).     

The Flynn effect in South Africa

This is a study of secular score gains in South Africa. The findings are based on representative samples from datasets utilized in norm studies of popular mainstream intelligence batteries such as the WAIS as well as widely used test batteries which were locally developed and normed in South Africa. Flynn effects were computed in three ways. First, studies where two different groups take the same test, with several years in between, using representative or comparable samples were used. Second, studies where the same group takes two different test batteries at a specific time were used. Third, the score differences between English- and Afrikaans-speaking Whites in South Africa in the 20th century were compared. The Flynn effect in White groups in South Africa is somewhat smaller than the Flynn effect in Western, industrialized countries (total N = 6534), and the Flynn effect in Indian groups is substantially smaller (total N = 682). Non-verbal IQ scores surpassed increases in verbal IQ scores. The findings from English- and Afrikaans-speaking Whites evidence a leveling out of differences in score gains over the 20th century (total N = 79,310). A meta-regression analysis showed no clear support for the moderators a) method used for computing the Flynn effect gain, b) type of test battery, c) time span, d) quality of the sample, and e) average age of sample.     

Intrapersonal Emotion Regulation Difficulties and Maladaptive Interpersonal Behavior in Adolescence

Research on Child and Adolescent Psychopathology - Although most research conceptualizes emotion regulation as an internal process (i.e., intrapersonal), emotions are frequently regulated in an...     

Were the Victorians cleverer than us? The decline in general intelligence estimated from a meta-analysis of the slowing of simple reaction time

The Victorian era was marked by an explosion of innovation and genius, per capita rates of which appear to have declined subsequently. The presence of dysgenic fertility for IQ amongst Western nations, starting in the 19th century, suggests that these trends might be related to declining IQ. This is because high-IQ people are more productive and more creative. We tested the hypothesis that the Victorians were cleverer than modern populations, using high-quality instruments, namely measures of simple visual reaction time in a meta-analytic study. Simple reaction time measures correlate substantially with measures of general intelligence (g) and are considered elementary measures of cognition. In this study we used the data on the secular slowing of simple reaction time described in a meta-analysis of 14 age-matched studies from Western countries conducted between 1889 and 2004 to estimate the decline in g that may have resulted from the presence of dysgenic fertility. Using psychometric meta-analysis we computed the true correlation between simple reaction time and g, yielding a decline of − 1.16 IQ points per decade or − 13.35 IQ points since Victorian times. These findings strongly indicate that with respect to g the Victorians were substantially cleverer than modern Western populations.     

Increased spreading activation in depression

The dopaminergic system is implicated in depressive disorders and research has also shown that dopamine constricts lexical/semantic networks by reducing spreading activation. Hence, depression, which is linked to reductions of dopamine, may be associated with increased spreading activation. However, research has generally found no effects of depression on spreading activation, using semantic priming paradigms. We used a different paradigm to investigate the relationship between depression and spreading activation, one based on word frequencies. Our sample included 97 undergraduates who completed the BDI-II and the Controlled Oral Word Association test as well as the Animal Naming test. The results indicated that the group scoring within the depressed ranged evidenced greater spreading activation as compared to those who scored within the normal range on the BDI-II. The implications of these results as they relate to creativity in depression is discussed.