# Negative Associations between Corpus Callosum Midsagittal Area and IQ in a Representative Sample of Healthy Children and Adolescents

 Title: Negative Associations between Corpus Callosum Midsagittal Area and IQ in a Representative Sample of Healthy Children and Adolescents Author: Ganjavi, Hooman; Bellec, Pierre; MacDonald, Penny A.; Evans, Alan C.; Karama, Sherif; Lewis, John D.; Waber, Deborah Paula Note: Order does not necessarily reflect citation order of authors. Citation: Ganjavi, Hooman, John D. Lewis, Pierre Bellec, Penny A. MacDonald, Deborah P. Waber, Alan C. Evans, and Sherif Karama. 2011. Negative associations between corpus callosum midsagittal area and IQ in a representative sample of healthy children and adolescents. PLoS ONE 6(5): e19698. Full Text & Related Files: 3098246.pdf (807.9Kb; PDF) Abstract: Documented associations between corpus callosum size and cognitive ability have heretofore been inconsistent potentially owing to differences in sample characteristics, differing methodologies in measuring CC size, or the use of absolute versus relative measures. We investigated the relationship between CC size and intelligence quotient (IQ) in the NIH MRI Study of Normal Brain Development sample, a large cohort of healthy children and adolescents (aged six to 18, n = 198) recruited to be representative of the US population. CC midsagittal area was measured using an automated system that partitioned the CC into 25 subregions. IQ was measured using the Wechsler Abbreviated Scale of Intelligence (WASI). After correcting for total brain volume and age, a significant negative correlation was found between total CC midsagittal area and IQ (r = −0.147; p = 0.040). Post hoc analyses revealed a significant negative correlation in children (age<12) (r = −0.279; p = 0.004) but not in adolescents (age $$\geq$$ 12) (r = −0.005; p = 0.962). Partitioning the subjects by gender revealed a negative correlation in males (r = −0.231; p = 0.034) but not in females (r = 0.083; p = 0.389). Results suggest that the association between CC and intelligence is mostly driven by male children. In children, a significant gender difference was observed for FSIQ and PIQ, and in males, a significant age-group difference was observed for FSIQ and PIQ. These findings suggest that the correlation between CC midsagittal area and IQ may be related to age and gender. Published Version: doi://10.1371/journal.pone.0019698 Other Sources: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3098246/pdf/ Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:10265016 Downloads of this work: