Hemisphere size asymmetry predicts relative verbal and nonverbal intelligence differently in the sexes: An MRI study of structure—Function relations

Hemispheric size asymmetry differences as assessed from MRIs of 39 healthy college students were correlated with prorated WAIS-R Verbal IQ minus Performance IQ and Vocabulary minus Block Design scores within subjects. In men, a relatively larger left hemisphere predicted better verbal than nonverbal ability, whereas in women a larger left hemisphere predicted relatively better nonverbal than verbal ability. The results were interpreted as providing evidence for sex differences in brain organization.