There is more into 'doing' than 'knowing': The function of the right inferior frontal sulcus is specific for implementing versus memorising verbal instructions

In the present study we examine the mechanism underlying the human ability to implement newly instructed stimulus-response mappings for their future application. We introduce a novel procedure in which we can investigate the processes underlying such implementation while controlling for more general working-memory demands. The results indicate that a region within the dorso-lateral prefrontal cortex (DLPFC) in the vicinity of the inferior frontal sulcus (IFS) is specifically recruited when new instructions are implemented compared to when new instructions are memorised. In addition, we observed that this area is more strongly activated when task performance is effective. Together, these findings suggest that the DLPFC, and more specific the IFS, plays an important role during the formation of procedural representations in working memory.