Understanding the Simber Effect: Why is the age-dependent increase in children's cognitive ability smaller in Arab countries than in Britain?

Abstract

Previous research indicates that the typical increase in IQ during childhood is greater in European countries than in Arab countries. A systematic literature review of age-dependent IQ in Arab countries is conducted, yielding relevant studies for 12 countries that fulfil the inclusion criteria. In almost all of these studies, Arab children exhibit an age-dependent IQ decline relative to Caucasian children, from 5 to about 12 years of age in particular. We term this phenomenon the Simber Effect. We propose two non-exclusive explanations. (1) The Flynn Effect is less intense in Arab countries because of localised differences, including poorer education quality and greater religiosity. (2) Those from Arab countries follow a faster Life History Strategy than Europeans, for environmental and possibly genetic reasons. Either way, the Simber Effect may amount to a Wilson Effect, meaning that the impact of genetic IQ increases with age.