Objective:Evidence about the etiology of the predictive associations between a
diagnosis of ADHD and cognitive performance over time is scarce. Here, we
examine these predictive and etiological patterns using a cross-lagged model
design in a sample of 404 participants (74% males) from ADHD and control
sibling pairs aged 6 to 17 years at baseline and 12 to 24 years at
follow-up.Methods:Data included IQ, short-term and working memory measures, and response speed
and variability from a four-choice reaction-time task.Results:ADHD and IQ predicted each other over time. ADHD at baseline predicted lower
working memory performance at follow-up. Stable etiological influences
emerged in the association between ADHD and cognitive variables across
time.Conclusion:Whether early interventions can reduce negative interference with learning at
school requires further study.