New research has settled an historical debate that the larger the brain the brighter the individual.
Michael McDaniel, an industrial and organizational psychologist, at Virginia Commonwealth University says that there is a direct correlation between intelligence and brain size.
McDaniel in his study used data from another 26 studies where subjects' brain volume was measured using MRI technology and the participants also took standard intelligence tests.
He says he found that for all age and sex groups, it was very clear that brain volume and intelligence are related.
According to McDaniel, his research is important because it answers critics of IQ tests.
McDaniel says that when intelligence is correlated with a biological reality such as brain volume, it becomes harder to argue that human intelligence can not be measured or that the scores do not reflect something meaningful.
The study has been published on line in the journal Intelligence.