The negative Flynn Effect: A systematic literature review

Flynn effect and its reversal are both environmentally caused

Population intelligence quotients increased throughout the 20th century-a phenomenon known as the Flynn effect-although recent years have seen a slowdown or reversal of this trend in several countries. To distinguish between the large set of proposed explanations, we categorize hypothesized causal factors by whether they accommodate the existence of within-family Flynn effects. Using administrative register data and cognitive ability scores from military conscription data covering three decades of Norwegian birth cohorts (1962-1991), we show that the observed Flynn effect, its turning point, and subsequent decline can all be fully recovered from within-family variation. The analysis controls for all factors shared by siblings and finds no evidence for prominent causal hypotheses of the decline implicating genes and environmental factors that vary between, but not within, families.

Toward an Integrated Cognition Perspective on Ethnic Prejudice

Both ability and motivation aspects of cognition have been shown to relate to ethnic prejudice. In line with recent theorizing, the present study advances an integrated cognition perspective on ethnic prejudice by examining the interplay between cognitive ability (measured with the Kaufman Adolescent and Adult Intelligence Test) and cognitive motivation (measured with the Need for Cognitive Closure [NFC] Scale) in a Belgian, heterogeneous adult sample ( N = 315). Path analysis revealed that intelligence and NFC each have unique and independent effects on ethnic prejudice, and that both right-wing authoritarianism and essentialist thinking play a mediating role in these effects. Hence, although cognitive abilities and motivations are to some extent interrelated and operate in similar ways, they uniquely and additively contribute to the explained variance in ethnic prejudice.