The Dynamic Associations Between Cortical Thickness and General Intelligence are Genetically Mediated

Cereb Cortex. 2019 Dec 17;29(11):4743-4752. doi: 10.1093/cercor/bhz007.


The neural substrates of intelligence represent a fundamental but largely uncharted topic in human developmental neuroscience. Prior neuroimaging studies have identified modest but highly dynamic associations between intelligence and cortical thickness (CT) in childhood and adolescence. In a separate thread of research, quantitative genetic studies have repeatedly demonstrated that most measures of intelligence are highly heritable, as are many brain regions associated with intelligence. In the current study, we integrate these 2 streams of prior work by examining the genetic contributions to CT-intelligence relationships using a genetically informative longitudinal sample of 813 typically developing youth, imaged with high-resolution MRI and assessed with Wechsler Intelligence Scales (IQ). In addition to replicating the phenotypic association between multimodal association cortex and language centers with IQ, we find that CT-IQ covariance is nearly entirely genetically mediated. Moreover, shared genetic factors drive the rapidly evolving landscape of CT-IQ relationships in the developing brain.

Trial registration: NCT00001246.

Keywords: MRI; cortical thickness; genetics; intelligence; neurodevelopment.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Twin Study

MeSH terms

  • Adolescent
  • Cerebral Cortex / anatomy & histology*
  • Cerebral Cortex / growth & development
  • Cerebral Cortex / physiology*
  • Child
  • Connectome
  • Female
  • Humans
  • Intelligence / genetics*
  • Magnetic Resonance Imaging
  • Male
  • Phenotype
  • Wechsler Scales
  • Young Adult

Associated data