Distributed brain sites for the g-factor of intelligence.
The general factor of intelligence (g) results from the empirical fact that almost all cognitive tests are positively correlated with one another. Individual tests can be classified according to the degree to which they involve g. Here, regional brain volumes associated with g are investigated by means of structural magnetic resonance imaging and voxel-based morphometry. First, individual differences in the amount of regional gray matter volumes across the entire brain were correlated with eight cognitive tests showing distinguishable g-involvement. Results show that increasing g-involvement of individual tests was associated with increased gray matter volume throughout the brain. Second, it is shown that two prototypical measures of verbal and non-verbal g (i.e., vocabulary and block design) correlate with the amount of regional gray matter across frontal, parietal, temporal, and occipital lobes, suggesting that the general factor of intelligence relates to areas distributed across the brain as opposed to the view that g derives exclusively from the frontal lobes.
Colom
Roberto
R
Facultad de Psicología, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
Jung
Rex E
RE
Haier
Richard J
RJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000033:anatomy & histology*; D002540:Cerebral Cortex / Q000033:anatomy & histology; D004292:Dominance, Cerebral / Q000502:physiology; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007360:Intelligence / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008432:Mathematical Computing; D008875:Middle Aged; D011594:Psychometrics / Q000706:statistics & numerical data; D013223:Statistics as Topic; D014888:Wechsler Scales / Q000706:statistics & numerical data*