Age-related changes in hemispheric asymmetry depend on sex

A total of 92 participants, 50 younger (mean age 26.3 years) and 42 older (mean age 63.8 years), were tested for visual-field asymmetries. On a word-matching task, a right-visual-field (RVF) advantage increased with age, consistent with the theory that right-hemispheric function shows relatively greater decline with age than left-hemispheric function. On a figural-comparison task, a left-visual-field (LVF) advantage was marginally decreased with age in the men, but significantly increased in the women, probably because age-related changes in hormonal levels are more pronounced in women. This increase in LVF advantage is contrary to both the HAROLD theory that hemispheric asymmetry declines with age, and the theory of relative right-hemispheric decline.