Praising or keeping silent on partner's ideas: Leading brainstorming in particular ways.

This study aimed to investigate how different feedback affect group creative performance, and reveal the underlying interpersonal neural correlates using the functional near-infrared spectroscopy (fNIRS)-based hyperscanning technique. Participants solved one creativity task with two strangers in conditions with positive/negative/no feedback. Results revealed that performance in the negative condition was lower than in the other conditions. Moreover, results showed the highest 'index of convergence'/collective flexibility in the positive/control condition respectively. The fNIRS results demonstrated IBS increment in the frontopolar and bilateral dorsolateral prefrontal cortex, which was stronger in the positive and negative conditions. The IBS increment in the frontopolar and bilateral DLPFC covaried with group creative performance in the positive condition. The findings indicated that negative feedback suppressed the group creative performance; whereas no feedback facilitated collective flexibility and positive feedback promoted interpersonal interaction, these two feedback conditions both benefited group creative performance.