1043-3155 Pediatr Neurol Briefs pedneurbriefs Pediatr Neurol Briefs Pediatric Neurology Briefs Pediatr Neurol Briefs 2166-6482 1043-3155 2166-3155 Pediatric Neurology Briefs Publishers Chicago, IL, USA PNB-12-48-a 10.15844/pedneurbriefs-12-6-13 Learning Disorders Neurology Pediatrics Nervous System Diseases Child Development Brain Diseases Neurosurgery Child Infant Brain Size or Brain Organization and Intelligence http://orcid.org/0000-0002-0173-7931 Millichap J. Gordon MD 1 2 * Division of Neurology, Children's Memorial Hospital, Chicago, IL Departments of Pediatrics and Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL Correspondence: Dr. J. Gordon Millichap, E-mail: jgmillichap@northwestern.edu 06 1998 01 05 2016 12 6 48 48 Copyright: © 1998 The Author(s) 1998 This work is licensed under the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Brain size, head size, and intelligence quotient in monozygotic twins

The relationship of head size and intelligence quotient (IQ) to neuroanatomic similarities in young, healthy adult monozygotic (MZ) twins was examined using MRI and quantitative image analysis at the Department of Neurobiology, Harvard Medical School, Boston, MA.

 Intelligence Quotient Monozygotic Callosal Area

The relationship of head size and intelligence quotient (IQ) to neuroanatomic similarities in young, healthy adult monozygotic (MZ) twins was examined using MRI and quantitative image analysis at the Department of Neurobiology, Harvard Medical School, Boston, MA. Significant effects of genotype but not birth order were found for the following measures: forebrain volume, cortical surface area, callosal area, head circumference, and full-scale IQ Forebrain volume, cortical surface area, callosal area, and each brain measure and head circumference were correlated, but not IQ. [1]

COMMENT. Brain measures in monozygotic twins are correlated with head circumference and brain volume but not with intelligence quotients. Intellectual similarities in MZ twins are not related to genetic influences on brain size (“bigger is ‘not’ better”) but rather, brain organization. Intellectual functions are correlated with regional brain measures and local geometry of folds in the left cerebral cortex and forebrain, areas that govern language and abstract reasoning.

Tramo MJ Loftus WC Stukel TA Green RL Weaver JB Gazzaniga MS Brain size, head size, and intelligence quotient in monozygotic twins Neurology 1998 May 50 5 1246 52 9595970 10.1212/WNL.50.5.1246