Abstract
The psychological construct "flow" has received major attention during the last decade by various scientific branches in the fields of psychology and neuroscience. Flow is operationally defined in relation to the boundary conditions of boredom and overload. According to the conditions' arrangement, two major neural flow effects are of interest, inferred by quadratic trends of neural activation. The inverted U-shaped pattern of neural activation is characterized by greater neural activation during the flow condition relative to boredom and overload, while the U-shaped pattern is the reverse, that is, lower neural activation during flow relative to its boundary conditions. Both effects have repeatedly been reported during the last years and have seen greater scientific resonance, which is why we found it necessary to try to replicate recent findings. A fresh sample of 41 healthy male participants was investigated with BOLD functional magnetic resonance imaging in combination with our flow paradigm. Electrodermal activation served as read-out of the flow effect on the psychophysiological level. Evidence of replication was quantified in terms of the replication Bayes factor. We observed strong replication evidence for electrodermal activation and decisive evidence of replication for both neural flow effects. Aspects of dorsolateral prefrontal cortex, anterior insula and parietal cortex showed inverted U-shaped activation. U-shaped activation was predominant in aspects of medial prefrontal cortex, ventral striatum, amygdala and along the cingulate cortex (subgenual, middle and posterior). Despite its strong replicability, the flow paradigm has been administered in men-only samples so far. Therefore, present results still await empirical replication in women-only samples.