Environmental sensitivity, developmental-context and sustained attention

This project, led by Katie Daubney, is attempting to address four research questions within the theoretical framework of Differential Susceptibility Theory:
- Is there a single factor of ‘sensitivity’?
- Where does it emerge?
- Is it moulded into ‘vantage’ or ‘vulnerability’ by the developmental context?
- Do those who are more sensitive and raised in a ‘positive’ environment do ‘better’ than those who are less sensitive and raised in a similar environment?
Children are not equally susceptible to environmental stimuli. However, contextual effects are still widely assumed to apply equally to all children despite the fact that individual characteristics may influence the role that early experiences have on child-development. Understanding the mechanisms involved in individual differences in context sensitivity may highlight the fact that optimum development may occur at varying levels of stimulation between individuals.
This study examines the interaction between individual differences in environmental sensitivity, the developmental context in which they emerge and how this affects early child development. Sensitivity has been measured in different ways, but for the first time, the extent to which measurements of autonomic sensitivity, neural sensitivity, negative and positive behavioural reactivity and temperament associate within infants will be examined to explore whether there is a single factor of sensitivity which varies between individuals.
Differential Susceptibility Theory suggests that while highly sensitive individuals may be more vulnerable to the ill effects of negative (risky) environments, they are also more capable than their more resilient counterparts to exploit the resources on offer in positive (supportive) environments (see fig.1).
Eighty mother-infant pairs visited the BabyLab when the infants were 6, 12 and 24-months old. Current analyses have shown weak associations between neural sensitivity and behavioural reactivity at 6m: the amplitude of the P3 to repeatedly-presented, standard tones negatively correlates with negative reactivity to toy retraction at 6m. This could be interpreted as sensory gating – a reduction in brain response to repeated sensory stimuli – correlating with better engagement with ‘tasks’ at 6m and therefore more appropriate/’effective’ responses. Further analyses will explore the strength of associations between all measures of sensitivity to ascertain whether there is evidence to support the idea that sensitivity is a unitary construct as well as the development of susceptibility to both positive and negative environmental effects.
Fig. 1. Differential Susceptibility Theory (Belsky, 2007; Ellis et al., 2005). For better and for worse.