This is an important update to Ulric Neisser et al.’s seminal 1996 article Intelligence: Knowns and unknowns. I had the privilege of seeing an early draft of this article and was impressed (I am in the acknowledgements for providing some feedback). This is a good up-to-date source if you want to know the latest in the field of human intelligence. For more up-to-date info on this topic, check out The Cambridge Handbook of Intelligence or IQ and Human Intelligence.
STUDY: Intelligence: New Findings and Theoretical Developments
AUTHORS: Richard E. Nisbett, Joshua Aronson, Clancy Blair, William Dickens, James Flynn, Diane F. Halpern, Eric Turkheimer
ABSTRACT:
We review new findings and new theoretical developments in the field of intelligence. New findings include the follow- ing: (a) Heritability of IQ varies significantly by social class. (b) Almost no genetic polymorphisms have been discovered that are consistently associated with variation in IQ in the normal range. (c) Much has been learned about the biological underpinnings of intelligence. (d) “Crystallized” and “fluid” IQ are quite different aspects of intelligence at both the behavioral and biological levels. (e) The importance of the environment for IQ is established by the 12-point to 18-point increase in IQ when children are adopted from working-class to middle-class homes. (f) Even when improvements in IQ produced by the most effective early childhood interventions fail to persist, there can be very marked effects on academic achievement and life outcomes. (g) In most developed countries studied, gains on IQ tests have continued, and they are beginning in the developing world. (h) Sex differences in aspects of intelligence are due partly to identifiable biological factors and partly to socialization factors. (i) The IQ gap between Blacks and Whites has been reduced by 0.33 SD in recent years. We report theorizing concerning (a) the relationship between working memory and intelligence, (b) the appar- ent contradiction between strong heritability effects on IQ and strong secular effects on IQ, (c) whether a general intelligence factor could arise from initially largely inde- pendent cognitive skills, (d) the relation between self-reg- ulation and cognitive skills, and (e) the effects of stress on intelligence.