Structural brain variation and general intelligence.
Total brain volume accounts for about 16% of the variance in general intelligence scores (IQ), but how volumes of specific regions-of-interest (ROIs) relate to IQ is not known. We used voxel-based morphometry (VBM) in two independent samples to identify substantial gray matter (GM) correlates of IQ. Based on statistical conjunction of both samples (N = 47; P < 0.05 corrected for multiple comparisons), more gray matter is associated with higher IQ in discrete Brodmann areas (BA) including frontal (BA 10, 46, 9), temporal (BA 21, 37, 22, 42), parietal (BA 43 and 3), and occipital (BA 19) lobes and near BA 39 for white matter (WM). These results underscore the distributed neural basis of intelligence and suggest a developmental course for volume--IQ relationships in adulthood.
Department of Pediatrics, University of California, Irvine, CA 92697-5000, USA. rjhaier@uci.edu
Richard J
RJ
Haier
Rex E
RE
Jung
Ronald A
RA
Yeo
Kevin
K
Head
Michael T
MT
Alkire
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000033:anatomy & histology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000033:anatomy & histology; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007206:Individuality; D007360:Intelligence / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008432:Mathematical Computing; D008875:Middle Aged; D012016:Reference Values; D012984:Software