Response modularity moderates how executive control aids fluent semantic memory retrieval.

Emerging work in semantic cognition has begun to elucidate the interaction between the structure of semantic memory and processes mediating goal-directed memory retrieval. Despite having essential implications for basic and applied research, these objectives remain neglected in both the assessment and interpretation of semantic verbal fluency (SVF) tasks. To test the association between semantic structure and the controlled processes underlying verbal fluency, we assessed how the degree of partitioning (modularity) of SVF responses into semantic clusters moderates the relationship of retrieval fluency with working memory and interference control capacities. We found that working memory capacity predicted retrieval fluency in individuals whose SVF responses were arranged in fine-grained semantic clusters (high modularity), whereas interference control was more predictive of retrieval fluency for individuals who delivered responses of low modularity. Our data support the presumed role of working memory and interference control in SVF and provide novel evidence that relative demands on these capacities are predicted by the organisation of semantic knowledge.