Intelligence Research Today is a free monthly online journal that collates and summarizes the latest research about Intelligence, including details on iq, testing, nature vs nurture, cognition.

Distributed brain sites for the g-factor of intelligence.

Colom R, Jung RE, Haier RJ

Facultad de Psicología, Universidad Autónoma de Madrid, 28049 Madrid, Spain.

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.

Published 16 June 2006 in Neuroimage, 31(3): 1359-65.
Full-text of this article is available online (may require subscription).

© 2005-2008 Intelligence Research Today. All Rights Reserved.