The main aim of this project was to explore to what extent genetic and environmental factors explain individual differences in brain development and cognition. The study was a part of a Dutch longitudinal study in which twins, their siblings and their parents were assessed at three years interval. This project included the measurement eight years after baseline, around the 17th birthday of the twins. Data collection included psychometric IQ tests, a comprehensive neuropsychological testing protocol, and parental and self-ratings of behavioral and emotional problems. Physical maturation was measured through assessment of Tanner stages. Hormonal levels were assessed in urine and saliva. Brain scans were acquired using 1.5 Tesla Magnetic Resonance Imaging (MRI), which provided volumetric measures and measures of cortical thickness. Buccal swabs were collected for DNA isolation for future genetic association studies.

Subject age
  • 17.0 years
Time span From 2012-01-01 to 2014-01-01
Geographic location NL
Dorret I. Boomsma
Vrije Universiteit Amsterdam
Suzanne Swagerman
Vrije Universiteit Amsterdam
Marinka Koenis
Universiteit Utrecht
Funding information
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