We published an editorial about the James Watson affair in November last year J. Rushton and A. We based our conclusion on 10 categories of research evidence. It was this evidence that Watson had at his disposal when making his claims about low African IQ test scores.
We studied a sample of 75 Chinese, 73 Malay, and 29 Indian healthy neonates taking part in a cohort study to examine potential differences in neonatal brain morphology and white matter microstructure as a function of ethnicity using both structural T2-weighted magnetic resonance imaging MRI and diffusion tensor imaging DTI. We first examined the differences in global size and morphology of the brain among the three groups. We then constructed the T2-weighted MRI and DTI atlases and employed voxel-based analysis to investigate ethnic differences in morphological shape of the brain from the T2-weighted MRI, and white matter microstructure measured by fractional anisotropy derived from DTI. Although most anatomical regions of the brain were similar among Chinese, Malay, and Indian neonates, there were anatomical variations in the spinal-cerebellar and cortical-striatal-thalamic neural circuits among the three populations. The population-related brain regions highlighted in our study are key anatomical substrates associated with sensorimotor functions. Research into early development has yet to fully examine the impact of population and population-related influences on brain morphology and microstructure, despite studies demonstrating population differences in the brains of adults.
The size of the brain is a frequent topic of study within the fields of anatomy and evolution. Brain size is sometimes measured by weight and sometimes by volume via MRI scans or by skull volume. Neuroimaging intelligence testing can be used to study the volumetric measurements of the brain.