This thesis uses a combination of cognitive-neurophysiological and genetically-sensitive longitudinal designs to study the associations of attention-deficit/hyperactivity disorder (ADHD) with bipolar disorder (BD) and preterm birth, as well as with the risk or protective factors IQ and physical activity. Previous research on preterm-born individuals and individuals with BD suggests ADHD-like symptoms and cognitive impairments, but direct comparisons are limited. Here, we first examine how cortical activity patterns differ between women with adult ADHD and women with BD during rest and task conditions to identify impairments that are specific to or shared between the disorders. The findings provide evidence for commonalities in brain dysfunction between ADHD and BD: frontal theta power may play a role as a marker of neurobiological processes in both disorders. Second, we investigate whether the ADHD-like symptoms and cognitive-neurophysiological impairments seen in preterm-born adolescents are identical to those in ADHD by directly comparing ADHD symptom scores and performance on a cognitive-neurophysiological test battery sensitive to impairments in ADHD across preterm-born adolescents, term-born adolescents with ADHD and term-born controls. We find that ADHD symptoms are increased in the preterm group compared to controls. The analyses further indicate similarities in brain function between ADHD and preterm birth, as well as unique impairments in the preterm group. Taken together, these results suggest that preterm birth may present a risk factor for both ADHD and additional impairments. Third, using twin data we carry out a developmental-genetic analysis of the association between ADHD and IQ, showing that ADHD symptoms and IQ scores significantly predict each other over time. Finally, we explore a putative protective factor for ADHD by investigating the effect of physical activity on ADHD symptoms. Using a population-based sample of twins, we show that physical activity is inversely associated with ADHD symptoms, even after adjusting for unmeasured confounding. Overall, we demonstrate certain commonalities in brain dysfunction between ADHD and BD. Whereas preterm birth and lower IQ present risk factors for ADHD, physical activity emerges as a potential protective factor.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:695717 |
| Date | January 2015 |
| Creators | Rommel, Anna Sophie |
| Contributors | Kuntsi, Jonna Pauliina ; Rijsdijk, Fruhling Vesta |
| Publisher | King's College London (University of London) |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | https://kclpure.kcl.ac.uk/portal/en/theses/a-cognitiveneurophysiological-investigation-of-adhd-associated-disorders-and-risk-or-protective-factors(37120855-35fa-4e68-a97d-d5ae69564bf6).html |
Page generated in 0.0023 seconds