The studies of this thesis provide empirical evidence that creativity is not a homogeneous concept; rather it reflects the interplay of separate, dissociable processes such as convergent and... Show moreThe studies of this thesis provide empirical evidence that creativity is not a homogeneous concept; rather it reflects the interplay of separate, dissociable processes such as convergent and divergent thinking (e.g., Guilford, 1967). The cognitive mechanism of these two processes is different, but not opposite as assumed by Eysenck (1993). The results suggest that divergent and convergent thinking are both related to dopamine, but to different degrees and in different ways. It was observed that eye-blink rate was predicting creative performance, which provides strong support for approaches that relate creativity to dopamine (Ashby et al., 1999). However, the obtained dissociation calls for a more differentiated approach that distinguishes between convergent and divergent processes and allows for tapping different creativity-dopamine functions. The findings of this thesis also suggest that convergent thinking induces a control state that emphasizes the top-down biasing of creative solutions and/or local competition between them, whereas divergent thinking is associated with reduced top-down control and/or local competition. Taken together, results of four studies presented in this thesis show that convergent and divergent thinking are not necessarily opposite but they are not the same either, and optimal performance in different types of creativity tasks requires different conditions. Show less
It is well known that complex mental abilities develop at least until late adolescence. Yet, there are also skills that children master perfectly, sometimes even better than adults. The goal of... Show moreIt is well known that complex mental abilities develop at least until late adolescence. Yet, there are also skills that children master perfectly, sometimes even better than adults. The goal of this thesis was to learn more about the possibilities of cognitive functioning in children and young adults, and the constraints set by the developing brain. An fMRI training approach was used to examine age- and experience-related effects in the development of working memory and resting-state functional connectivity. More specifically, we studied age differences on task performance and brain activation during a working memory task with various demands and difficulty levels, both before and after 6 weeks of practice with the task. In addition, to learn more about the interaction between different brain regions, we also examined age differences and practice effects on functional connectivity during resting-state. Show less
The studies described in this thesis address a range of topics related to arousal, exploration, temporal attention, and the locus coeruleus-norepinephrine (LC-NE) system. Chapters 2 and 3 report... Show moreThe studies described in this thesis address a range of topics related to arousal, exploration, temporal attention, and the locus coeruleus-norepinephrine (LC-NE) system. Chapters 2 and 3 report two studies that investigated a recent theory about the role of the LC-NE system in the regulation of the exploration-exploitation trade-off. Chapter 4 reports a study on neurocognitive function in patients with dopamine-β-hydroxylase (DβH) deficiency. Chapter 5 reports an fMRI study on the neural correlates of perceptual curiosity. Chapter 6 and 7 reported several experiments investigating the effects of ‘accessory stimuli’ and temporal certainty on information processing, using scalp electrophysiology and sequential-sampling models of decision making. Taken together, the studies reported in this thesis suggest that arousal, exploration and temporal attention are closely related, which is likely due to a shared neural basis. Show less