Thesis (MCurr)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The global epidemic of HIV continues with an estimated 2.2 million children under 15 years of age worldwide living with HIV and 640 000 newly infected in 2004 (WHO, 2009). HIV crosses the blood–brain barrier which may lead to neuronal damage and death. There is controversial evidence within available research on effects of HIV on cognitive and motor development in children because of the limitations imposed by study designs, study populations and study methodological quality. The aims of the review were: - To conduct a systematic review of published research to establish the effects and the prevalence of HIV infection on cognitive and motor development in children. - To critically appraise the methodological quality of published research regarding cognitive and motor development of HIV infected children. The objectives of the review were: - To assess evidence on the cognitive and motor development of HIV-1 infected children - To describe anthropometric outcomes including: weight for age, weight for height, height for age and head circumference in children with a HIV infection. - To assess the methodological quality of studies on the cognitive and motor development of HIV infected children. The following databases were searched for identification of articles; MEDLINE, Google Scholar, AIDSTRIALS, AIDSLINE and CINHAL. The search time frame included published works from inception to July 2011 without language restrictions. Analytical observational trials that assessed at least one outcome (cognitive or motor development or 1 of the anthropometric outcomes) between HIV positive and HIV negative children aged 5 years and below or children with a mean age of less than 5 years were employed. Two review authors independently searched for eligible studies, evaluated methodological quality and extracted the data. Meta-analysis was carried out using Rev Man 5.1 using the risk ratio for categorical data and standard mean difference for continuous data. Fifteen studies with a total of 3 086 participants met the inclusion criteria. HIV infected children were 2.45 times at higher risk of developing cognitive developmental delay than HIV negative children (RR, 95% CI, 1.95, 3.07, P < 0.00001). Infected children scored - 0.54 less than HIV negative children (SMD 95% CI, -0.70, -0.39, 97, p < 0.00001) for cognitive development and -0.68 in motor development (SMD 95% CI, -0.82, -0.55, p< 0.00001). The risk of motor developmental delays was 2.95 times in HIV positive compared with HIV negative children (RR 95% CI, 2.19, 3.99, p < 0.00001). HIV infected children are slower in aspects of cognitive and motor development compared to their HIV negative counterparts. They also showed delays in anthropometric outcomes; weight for age and height for age. Study design influenced results of the studies with children scoring more on cross sectional than cohort studies. There is still need to develop culturally appropriate or standardise neurodevelopment tools as most African studies still rely on international tools. More evidence is needed on the effectiveness of HAART in reducing cognitive and motor delay. / AFRIKAANSE OPSOMMING: Die wêreldwye MIV epidemie duur voort met ongeveer 2.2 miljoen kinders onder 15 jarige ouderdom wat wêreldwyd met MIV leef en 640 000 onlangs in 2004 geïnfekteerd (WHO, 2009). MIV strek oor die bloed-brein grens wat kan lei tot neuronale skade en die dood. Daar is kontroversiële bewys binne beskikbare navorsing oor die effek wat MIV het op kognitiewe en motoriese ontwikkeling in kinders, vanweë die beperkinge wat geplaas word deur studie ontwerpe, studie bevolkings en studie metodologiese kwaliteit. Die doelwitte van die oorsig is om - ‘n sistematiese oorsig van gepubliseerde navorsing te doen om sodoende die effek en voorkoms van MIV infeksie op kognitiewe en motoriese ontwikkeling by kinders vas te stel - ’n kritiese waardering van die metodologiese kwaliteit van gepubliseerde navorsing te doen ten opsigte van die kognitiewe en motoriese ontwikkeling van MIV geïnfekteerde kinders. Die doelwitte van die oorsig is om - assessering te doen van die bewyse van kognitiewe en motoriese ontwikkeling by MIV-1 geïnfekteerde kinders - antropometriese uitkomste te beskryf, insluitend: gewig vir ouderdom, gewig vir hoogte, hoogte vir ouderdom en omtrek van die hoof by kinders met ’n MIV infeksie - die metodologiese kwaliteit te assesseer van studies op die kognitiewe en motoriese ontwikkeling van MIV geïnfekteerde kinders. Die volgende databasisse is nagevors vir die identifisering van artikels: MEDLINE, Google Scholar, AIDSTRIALS, AIDSLINE en CINHAL. Die tydraamwerk vir navorsing het gepubliseerde werk ingesluit vanaf aanvang tot Julie 2011 sonder taalbeperkings. Analitiese waarneembare toetse wat ten minste een uitkoms geassesseer het (kognitiewe of motoriese ontwikkeling of 1 van die antropometriese uitkomste) tussen MIV positiewe en MIV negatiewe kinders van 5 jarige ouderdom en jonger, of kinders met ’n gemiddelde ouderdom van minder as 5 jaar is betrek. Twee oorsig outeurs het onafhanklik vir geskikte studies gesoek, metodologies geëvalueer en data getrek. Meta-analise was uitgevoer deur gebruik te maak van Rev Man 5.1 met behulp van die risiko-ratio vir kategoriese data en die standaard gemiddelde verskil vir aaneenlopende data. Vyftien studies met ’n totaal van 3 086 deelnemers met die insluitingskriteria. MIV geïnfekteerde kinders het 2.45 keer ’n hoër risiko gehad om kognitiewe ontwikkelingsvertraging te ontwikkel as MIV negatiewe kinders (RR, 95% CI, 1.95, 3.07, P< 0.0000). Geïnfekteerde kinders het ’n -0.54 telling behaal, minder as MIV negatiewe kinders (SMD 95% CI, -0.70, -0.39,97 p < 0.00001) vir kognitiewe ontwikkeling en -0.68 vir motoriese ontwikkeling (SMD 95% CI, -0.82, -0.55, p< 0.00001). Die risiko van motoriese ontwikkelingsvertragings was 2.95 keer by MIV positiewe in vergelyking met MIV negatiewe kinders (RR 95% CI, 2.19, 3.99. p < 0.00001). MIV geïnfekteerde kinders is stadiger in aspekte van kognitiewe en motoriese ontwikkeling in vergeyking met hulle MIV negatiewe eweknieë. Hulle het ook vertragings getoon in antropometriese uitkomste; gewig vir ouderdom en hoogte vir ouderdom. Studie ontwerpe het uitslae beïnvloed van die kinders wat ’n hoër telling behaal het met deursnee as in kohort studies. Daar is nog ’n behoefte om kultureel geskikte of gestandaardiseerde neuro-ontwikkelingsinstrumente te ontwikkel, omdat die meeste Afrika-studies nog steeds staat maak op internasionale instrumente. Meer bewyse is nodig aangaande die effektiwiteit van HAART om kognitiewe en motoriese vertraging te verminder.

Human sociality, with its wide scope, early ontogeny and pervasiveness across cultures, is remarkable from an evolutionary perspective. We form bonds with other individuals and live in large social groups. We help, empathise with and share our resources with others, who are unfamiliar and genetically unrelated to us. It has been suggested that interpersonal coordination and rhythmic synchronisation of movements may be one proximate mechanism that enables such widespread human sociality and facilitates cooperation. In the last decade, considerable research has examined the effect of movement synchrony on social bonding and cooperation. However, when this thesis started, there was virtually no experimental study investigating the ontogeny of the movement synchrony-social bonding link, which is proposed to have deep evolutionary roots and important, long-lasting consequences in social life. This thesis aims to investigate the effects of movement synchrony on social bonding and cooperative behaviour across different time points in ontogeny. Three experimental studies were conducted examining infancy, early childhood and middle childhood. Each study explored a different aspect of social bonding and cooperation based on the motor, social and cognitive developments that mark that age group. Study 1a found that at 12 months of age, infants prefer individuals who move in synchrony with them, when the individuals are social entities, but not when they are non-social. Study 1b showed no preferences for synchrony at 9 months in either social or non-social contexts, however. Study 2 revealed that in early childhood, performing synchronous movements actively with a peer facilitates helping behaviour among the children, as well as eye contact and mutual smiling during the interaction. Finally, Study 3 showed that the social bonding effects of movement synchrony applied to inter- group settings and that performing synchronous movements with out-groups increased bonding towards the out-group in middle childhood. This thesis followed an interdisciplinary, integrative and naturalistic approach, where (i) literature from a wide range of disciplines motivated and guided the present research; (ii) links between motor, social and cognitive aspects of development, which are often investigated separately, are formed; and (iii) the experiments were designed in ways that represent the real-life occurrences of the investigated phenomena. The current findings provide the first substantial evidence that movement synchrony facilitates social bonding and cooperation in childhood and thereby provides a foundation for future research.