Musical aptitude and music training are associated with language-related cognitive outcomes, even when controlling for general intelligence. However, genetic and environmental influences on these associations have not been studied, and it remains unclear whether music training can causally increase verbal ability. In a sample of 1,336 male twins, we tested the associations between verbal ability measured at time of conscription at age 18 and two music related variables: overall musical aptitude and total amount of music training before the age of 18. We estimated the amount of specific genetic and environmental influences on the association between verbal ability and musical aptitude, over and above the factors shared with general intelligence, using classical twin modelling. Further, we tested whether music training could causally influence verbal ability using a co-twin-control analysis. Musical aptitude and music training were significantly associated with verbal ability. Controlling for general intelligence only slightly attenuated the correlations. The partial association between musical aptitude and verbal ability, corrected for general intelligence, was mostly explained by shared genetic factors (50%) and non-shared environmental influences (35%). The co-twin-control-analysis gave no support for causal effects of early music training on verbal ability at age 18. Overall, our findings in a sizeable population sample converge with known associations between the music and language domains, while results from twin modelling suggested that this reflected a shared underlying aetiology rather than causal transfer.

In the present study we devised a novel coding scheme for responses generated in a divergent thinking task. Based on considerations from behavioural and neurocognitive research from an embodied perspective, our scheme aims to capture dimensions of simulations of action or the body. In an exploratory investigation, we applied our novel coding scheme to analyze responses from a previously published dataset of divergent thinking responses. We show that a) these dimensions are reliably coded by naïve raters, and that b) individual differences in creativity influences the way in which different dimensions are used over time. Overall, our results provide new hypotheses about the generation of creative response in the divergent thinking task and should serve to characterize the cognitive strategies used in creative endeavors.

Pictorial examples during creative thinking tasks can lead participants to fixate on these examples and reproduce their elements even when yielding suboptimal creative products. Semantic memory research may illuminate the cognitive processes underlying this effect. Here, we examined whether pictures and words differentially influence access to semantic knowledge for object concepts depending on whether the task is close- or open-ended. Participants viewed either names or pictures of everyday objects, or a combination of the two, and generated common, secondary, or ad hoc uses for them. Stimulus modality effects were assessed quantitatively through reaction times and qualitatively through a novel coding system, which classifies creative output on a continuum from top-down-driven to bottom-up-driven responses. Both analyses revealed differences across tasks. Importantly, for ad hoc uses, participants exposed to pictures generated more top-down-driven responses than those exposed to object names. These findings have implications for accounts of functional fixedness in creative thinking, as well as theories of semantic memory for object concepts.

Should executive control, as indicated by working memory capacity (WMC) and mind-wandering propensity, help or hinder creativity? Sustained and focused attention should help guide a selective search of solution-relevant information in memory and help inhibit uncreative, yet accessible, ideas. However, unfocused attention and daydreaming should allow mental access to more loosely relevant concepts, remotely linked to commonplace solutions. Three individual-differences studies inserted incubation periods into one or two divergent thinking tasks and tested whether WMC (assessed by complex span tasks) and incubation-period mind wandering (assessed as probed reports of task-unrelated thought [TUT]) predicted post-incubation performance. Retrospective self-reports of Openness (Experiment 2) and mind-wandering and daydreaming propensity (Experiment 3) complemented our thought-probe assessments of TUT. WMC did not correlate with creativity in divergent thinking, whereas only the questionnaire measure of daydreaming, but not probed thought reports, weakly predicted creativity; the fact that in-the-moment TUTs did not correlate divergent creativity is especially problematic for claims that mind-wandering processes contribute to creative cognition. Moreover, the fact that WMC tends to strongly predict analytical problem solving and reasoning, but may not correlate with divergent thinking, provides a useful boundary condition for defining WMC's nomological net. On balance, our data provide no support for either benefits or costs of executive control for at least one component of creativity.

Divergent thinking tasks are commonly used as indicators of creative potential, but traditional scoring methods of ideational originality face persistent problems such as low reliability and lack of convergent and discriminant validity. Silvia et al. (2008) have proposed a subjective top-2 scoring method, where participants are asked to select their two most creative ideas, which then are evaluated for creativity. This method was found to avoid problems with discriminant validity, and to outperform other scoring methods in terms of convergent validity. These findings motivate a more general, systematic analysis of the subjective top-scoring method. Therefore, this study examined how reliability and validity of the originality and fluency scores depend on the number of top-ideas and on time-on-task. The findings confirm that subjective top-scoring avoids the confounding of originality with fluency. The originality score showed good internal consistency, and evidence of reliability was found to increase as a function of the number of top-ideas and of time-on-task. Convergent validity evidence, however, was highest for a time-on-task of about 2 to 3 minutes and when using a medium number of about three top-ideas. Reasons for these findings are discussed together possible limitations of this study and future directions. The article also presents some general recommendations for the assessment of divergent thinking with the subjective top-scoring method.