The role of the prefrontal cortex in semantic control for selecting weakly associated meanings in creative idea generation

Although semantic control is known to play a critical role in selecting weakly associated representations for creative idea generation, direct evidence for this is still lacking. The current study aimed to reveal the role of brain regions, including the inferior frontal gyrus (IFG), medial frontal gyrus (MFG), and inferior parietal lobule (IPL), previously reported to be associated with creative idea generation. For this purpose, a functional MRI experiment with a newly developed category judgment task was conducted, which required participants to judge whether two words belonged to the same category. Importantly, weakly associated meanings were manipulated by the task condition, which required selecting an unused meaning of the homonym in a preceding semantic context. The results showed that the selection of a weakly associated meaning for a homonym was associated with an increased activation of the IFG and MFG and a decreased activation of the IPL. These results suggest that IFG and MFG contribute to semantic control processes recruited for the selection of weakly associated meanings and self-guided retrieval, whereas IPL appears to be unrelated to the control demand for creative idea generation.