Exploring the relationship between HIV and executive function in adolescents, and testing the feasibility of a music intervention aiming to improve executive function in HIV-positive adolescents in rural South Africa
Keywords: Africa
adolescent
executive function
HIV
risky behaviour
cognition

Executive function (EF) is an umbrella term for a group of related yet distinguishable cognitive functions responsible for flexibly controlling and directing attention and behaviour. EF is important in the top-down control of decision-making and the ability to direct attention towards the fulfilment of long-term goals. EF, particularly in emotive contexts, is still developing during adolescence. EF may also be affected negatively by various threats to optimal EF development, including depression and HIV infection. Immature or suboptimal EF may predispose to risk-taking behaviour, including risky sexual behaviour and substance use, which in turn increases the risk of HIV transmission and poorer health and socioeconomic outcomes.
I have three major hypotheses which are explored in this thesis. Firstly, I hypothesise that there is a relationship between HIV and poorer EF in adolescents. Secondly, I hypothesise that poorer EF is associated with increased risky sexual behaviour and substance use in adolescents, and lower adherence to treatment in HIV-positive adolescents. Thirdly, I propose that musical training, particularly group drumming, is a feasible and acceptable intervention to enhance EF and mood in HIV-positive adolescents.
The thesis begins with an introduction to the relevant concepts and background literature (Chapter 1) before presenting a systematic review and meta-analyses of EF in HIV-affected children and adolescents globally (Chapter 2). It then shifts to the region of interest, rural South Africa, and presents the validation of a tablet-based EF assessment tool (Chapter 3) followed by a cross-sectional study assessing the relationship between EF and risk-taking behavioural outcomes, including behaviourally acquired HIV, in late adolescent females (Chapter 4). Finally, musical training is explored as a potential intervention to improve EF. A literature review on musical training and EF, and the potential socio-emotional effects of group drumming (Chapter 5) provides the background to a feasibility trial assessing the feasibility and acceptability of a group drumming intervention aiming to improve EF in HIV-positive adolescents in rural South Africa (Chapter 6). The thesis concludes with a general discussion chapter which integrates the findings and considers potential future directions (Chapter 7).
Study 1 found evidence for EF deficits in perinatally acquired HIV; evidence was limited for behaviourally acquired HIV. Study 2 found that the OCS-EF is a valid and feasible tool for measuring EF reliably amongst adolescents in rural South Africa. Study 3 found that EF is only weakly associated with certain risky behavioural outcomes, and that adolescents with behaviourally acquired HIV may only have limited EF deficits relating to verbal working memory. Study 4 found that a group drumming programme is a feasible and acceptable intervention amongst HIV-positive adolescents in rural South Africa, with promising effects on psychosocial wellbeing, including mood, but no effects on EF.