Assessing infant neurocognitive development in resource-poor settings: the example of memory development in the UK and The Gambia

Infants and children in low and middle income countries (LMIC’s) are at increased risk of compromised neurodevelopmental outcomes, due to exposure to a range of environmental risk factors. Neurocognitive research to date has focused almost exclusively on western, industrialised settings. For this reason, there is a lack of knowledge on what constitutes normative neurocognitive development in LMIC’s. By understanding infant development more globally, an opportunity is created which ultimately will enable early intervention, targeting specific risk factors commonly encountered in LMIC settings. This project assesses neurocognitive development in early infancy, with a particular focus on memory functioning. Infants were longitudinally examined in both the UK and in a rural village in The Gambia, West Africa. Assessments were conducted at 1, 5, 8 and 12 months of age using both neuroimaging measures (electroencephalography, functional near infrared spectroscopy) and behavioural methods. Findings across these studies indicate differential developmental trajectories between the two cohorts. Electrophysiological measures indicate an attenuated developmental change in the Gambian cohort between 1 and the 5 months of age. Cortical haemodynamic responses differed between cohorts, in terms of their localisation and magnitude. Behaviourally, higher levels of retention of novel actions were observed in the UK compared to the Gambian cohort. This thesis is part of one of the first projects taking a global perspective on early neurocognitive development, by exploring infants in a previously understudied population. The implementation of novel, objective neuroimaging methods has yielded results indicative of striking differences between the two cohorts. These data will provide a basis for future projects aimed at implementing interventions and thus alleviating some of the global burden of suboptimal neurocognitive development