Is there still a cognitive cost of being a twin in the UK?

ObjectiveTo investigate whether twins still perform below singletons in cognitive ability tests and in national educational attainment examinations in a recent UK cohort of 11-year-olds.DesignPopulation-based cohort study, using a validated method of twin extraction.SettingEnglish state schools.Participants178,599 pupils (mean age 11 years) attending English state schools in 2004, representing 93% of local educational authorities.Main outcome measuresVerbal, quantitative and nonverbal reasoning measured by the Cognitive Abilities Test — Third Edition (CAT3), and educational attainment in English, maths and science from Key Stage 2 national curriculum tests.ResultsTwin-singleton differences in cognitive ability were of negligible effect size. Mean performance of twins was 1% of a SD below singletons on general cognitive ability, 3% lower on verbal reasoning, and less than 1% of a SD lower on quantitative and nonverbal reasoning, with and without adjustment for sex. Almost identical proportions of twins and singletons attained the expected standards of educational performance in English (80.4% versus 80.5%, respectively), maths (77.4% versus 77.3%), and science (90.1% versus 88.8%). There were no differences in rates of twins and singletons achieving higher or lower performance levels.ConclusionThe cognitive cost of being a twin reported in previous cohorts of UK children no longer exists in a large, contemporary and population-representative sample.     

Theorizing Politics After Camus

Theorizing has been conceived historically in illuminative and ocular metaphors, and as an activity that occurs in a fixed and privileged relation to political society that permits a panoramic perspective. These elements of light, sight, and distance, are supportable existentially and ethically in post-war, post-Holocaust world. One of the first to explore the challenges to theorizing in this era was Albert Camus. He provided phenomenological and existential investigations of the obstacles to theorizing politics in his literary works, particularly his trilogy of novels: The Stranger, The Plague, and The Fall. In this paper, I offer a reading of these novels that isolates theorizing as an activity performed not from a transcendent perceptual vantage of perfect light and vision, but from the immanent perspectives achieved in the city, among friends, or by exile.     

Assessing the Functions of Non-suicidal Self-injury: Psychometric Properties of the Inventory of Statements About Self-injury (ISAS)

The present study reports the psychometric properties of the Inventory of Statements About Self-injury (ISAS), a measure designed to comprehensively assess the functions of non-suicidal self-injury (NSSI). The ISAS assesses 13 functions of NSSI, as well as the frequency of 12 NSSI behaviors. The ISAS was administered to 235 young adults from a college population who had performed at least one NSSI behavior. Consistent with previous research, ISAS functions comprised two factors representing interpersonal and intrapersonal functions. In addition, the ISAS factors exhibited excellent internal consistency and expected correlations with both clinical constructs (e.g., borderline personality disorder, suicidality, depression, anxiety) and contextual variables (e.g., tendency to self-injure alone). Findings support the reliability and validity of the ISAS. The ISAS may be useful in research and treatment contexts as a comprehensive measure of NSSI functions.     

Children's understanding of the inverse relation between multiplication and division

Children's understanding of the inversion concept in multiplication and division problems (i.e., that on problems of the form d * e/e no calculations are required) was investigated. Children in Grades 6, 7, and 8 completed an inversion problem-solving task, an assessment of procedures task, and a factual knowledge task of simple multiplication and division. Application of the inversion concept in the problem-solving task was low and constant across grades. Most participants approved of the inversion-based shortcut but only a slight majority preferred it. Three clusters of children were identified based on their performance on the three tasks. The inversion cluster used and approved of the inversion shortcut the most and had high factual knowledge. The negation cluster used the negation strategy, had lower approval of the inversion shortcut, and had medium factual knowledge. The computation cluster used computation and had the lowest approval and the weakest factual knowledge. The findings highlight the importance of addressing the multiplication and division inversion concept in theories of children's mathematical competence.     

When do children learn from unreliable speakers?

Children do not necessarily disbelieve a speaker with a history of inaccuracy; they take into account reasons for errors. Three- to five-year-olds (N = 97) aimed to identify a hidden target in collaboration with a puppet. The puppet’s history of inaccuracy arose either from false beliefs or occurred despite his being fully informed. On a subsequent test trial, children’s realistic expectation about the target was contradicted by the puppet who was fully informed. Children were more likely to revise their belief in line with the puppet’s assertion when his previous errors were due to false beliefs. Children who explained this puppet’s prior inaccuracy in terms of false belief were more likely to believe the puppet than those who did not. As children’s understanding of the mind advances, they increasingly balance the risk of learning falsehoods from unreliable speakers against that of rejecting truths from speakers who made excusable errors.     

Socioenvironmental experiences,self-esteem,and emotional/behavioral problems in early adolescence

Tested the role of self-esteem as a mediator of relationships between socioenvironmental experiences and emotional/behavioral problems using a sample of 215 young adolescents (Grades 7–9). Socioenvironmental experiences were assessed using self-report questionnaire measures of social support and major and minor stressful events. Self-esteem was assessed using a self-report questionnaire, an interview, and a parent-report questionnaire. Emotional/behavioral problems were assessed using self-report, parent-report and teacherreport questionnaires. Utilizing structural equation modeling, the data were used to test a model in which self-esteem mediated the relationship between socioenvironmental experiences and emotional/behavioral problems. The hypothesized model provided a reasonably good fit to the data (normed fit index=.90). However, an alternative model which also allowed for direct effects of socioenvironmental experiences on emotional/behavioral problems produced a significant improvement in model fit. In this model, socio-environmental experiences had significant effects on emotional problems via both direct effects and indirect effects that indicated a mediating role for self-esteem. Only direct effects of socioenvironmental experiences were evident for behavioral problems. This research was supported by a grant to the first author from the University of Missouri Research Board. Thanks are due to the students, staff, and parents of the Columbia Public Schools, Columbia, Missouri, for their participation in and support of this research project.