Cognitive control development in adolescence

Adolescence is a transitional period in which an increasing ability to coordinate basic cognitive control abilities is also particularly challenged by contextual factors in the environment. The aim of this dissertation was to examine the development of complex cognitive control in adolescence in relation to different socio-affective contexts at the behavioural and neural level. The dissertation presents three functional magnetic resonance imaging (fMRI) experiments. The first studies explored transient and sustained aspects of cognitive control, and how the context influences behaviour and brain activation during cognitive control tasks. Study 1 used a prospective memory task where the cues were more or less salient, affecting the need to proactively monitor the stimuli vs. react to more distinctive cues. Study 2 used a working memory task and manipulated the reward context, on a trial-by-trial or run-by-run basis. Study 3 used a relational reasoning task to investigate manipulation and integration of information and its sensitivity to the nature of this information, in particular whether making judgements in the social domain elicited specific brain activations compared to the non-social domain. All three studies were run in adolescent and adult participants, to allow the study of developmental changes in complex cognitive control at the behavioural and brain level. Study 1 found behavioural evidence for development of prospective memory in adolescence and neuroimaging evidence for sustained and transient activation of the frontoparietal network associated with monitoring costs for cue detection whilst being engaged in a different task. Study 2 found that in the context of sporadic rewards, both adolescents and adults combine a proactive and a reactive strategy to maximise performance. Reward had both sustained and transient effects on frontoparietal regions as well as subcortical regions involved in reward processing. Study 3 showed parallel recruitment of the social brain and the relational reasoning network during the relational integration of social information in adolescence and adulthood. Across the three studies, there was evidence for behavioural improvement with age, but no strong differences of haemodynamic brain changes between adolescence and adulthood