AUTHOR=Wood Alexis C., Rijsdijk Fruhling , Asherson Philip , Kuntsi Jonna TITLE=Inferring Causation from Cross-Sectional Data: Examination of the Causal Relationship between Hyperactivity–Impulsivity and Novelty Seeking JOURNAL=Frontiers in Genetics VOLUME=volume 2 - 2011 YEAR=2011 URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2011.00006 DOI=10.3389/fgene.2011.00006 ISSN=1664-8021 ABSTRACT=Previous research suggests an association between hyperactivity-impulsivity – one of the two behavioural dimensions that form attention deficit hyperactivity disorder – and the temperament characteristic of novelty seeking. We aimed to examine etiological links underlying the co-occurrence between these behaviours using a general population sample of 668 twin pairs, ages 7-10, for whom we obtained parent ratings in middle childhood; and pilot longitudinal data on 76 children. Structural equation modelling confirmed a shared genetic etiology (genetic correlation, rD=.81; 95% confidence intervals [CI]= .34-1.00) and showed that much (64%) of the covariation can be accounted for by shared genetic effects. In addition, causal paths were modelled between the two behaviours; 12% of the variance in novelty seeking at age 7 was accounted for by hyperactive-impulsive behaviors at the same age. The causal effects model fits with the current characterization of hyperactive-impulsive behaviors reflecting a heightened need for stimulation. This has important implications for the management of hyperactive-impulsive behaviors in clinical settings.