AbstractExecutive Function (EF) deficits are evidenced in children with behavioural difficulties. Yet, it is not clear how specific executive processes impact maladaptive behaviour in this population. What is more, previous research suggests that not only are EF and emotion regulation (ER) intrinsically linked to behaviour difficulties, but evidence also indicates that emotionally salient contexts have a negative impact on such processes which allow a person to control their behaviour. Therefore, efforts to examine how these control processes are impaired in different situations or contexts are presented in this thesis.
Understanding the structure of EF in typically developing children is an important first step in examining the relationship of executive dysfunction and behaviour difficulties in atypical child populations. Therefore, the first endeavour of this work addressed the unresolved EF structure during development at a neural level, through a meta-analysis of functional magnetic resonance imaging (fMRI) data of 1,177 typically developing children across 53 studies. Results indicated a structural model with both common and distinctive EF processes, as found in adults, can be applied to children. However, separable updating and switching processes were more apparent when adolescents were considered alongside children, suggesting distinction of these specific executive processes may occur later in development. A secondary meta-analysis, utilising the same data followed, which examined activation pertaining to task-specific components of EF engagement. Results show executive tests involving visual letter stimuli (when compared to arrow, pictorial or spatial stimuli) recruited a particularly large proportion of common EF, and updating activation maps. Further, through assessing their contribution at a neural level to common EF, it was possible to rank inhibition tests. These findings not only contributed to the task-impurity problem but informed the development of a new online EF battery, which was subsequently administered to children in the main empirical study presented in chapter 5.
The work presented in chapters 4 and 5 investigated emotionally salient contexts which elicit clinically relevant behaviours, and the effect these contexts have on EF and ER, in 63 children across the diagnostic spectrum who presented with internalising and externalising behaviour. Parental interview data regarding contexts that most negatively impact their child’s behaviour revealed two clinically meaningful groups, that is- children who were more negatively affected by situations which threaten their self-concept, and children who were more negatively affected by situations which do not threaten their self-concept. Logistic regression analyses were carried out to examine if specific EF and ER profiles predict membership into our contextually specified groups. Results indicated significant interactions between EF (at multiple levels) and maladaptive ER in predicting context group classification. However, no corresponding significant results pertaining to membership of diagnostic groups were found, suggesting that contextual factors and the impact they have on control processes, may be more important than diagnostic status, when considering behavioural change. Importantly, findings also demonstrate that updating deficits contribute to impairment in contexts which support a negative self-concept, which further exacerbate engagement in self-focused maladaptive ER. Therefore, further consideration of the role updating plays in self-focused ER and in turn, behaviour difficulties in children, is needed, which may inform important tailored intervention work for this population.
|Date of Award||2019|
|Supervisor||Kate Woodcock (Supervisor) & Teresa Rushe (Supervisor)|