News Finding: The reasons behind the changes in IQ are not clear at this point.
Paper Finding: Importantly, and contrary to conclusions, the association between cortical and cognitive changes in our data was found in brain areas that are relevant for individual differences in general intelligence.
News Context: This finding should make people wary of sticking to an early IQ assessment given the role it plays in school entrance criteria, detection of the gifted, as well as in eligibility for social security disability income or even the death penalty. The reasons behind the changes in IQ are not clear at this point. Some of these may be due to programmed developmental trajectories or other factors such as nutrition and education, noted Professor Karama.
Paper Context: Differences between voxel and surface-based morphometry techniques, as well as other methodological differences (e.g., sample size, cognitive tests used, sample representativeness) are likely partly to account for the observed discrepancies. Importantly, and contrary to conclusions, the association between cortical and cognitive changes in our data was found in brain areas that are relevant for individual differences in general intelligence. The associations we observed in sensorimotor areas deserve further study, although they are consistent with extensive evidence showing that the sensorimotor cortex is involved in abstract reasoning, a main subcomponent of general cognitive ability.