Common prefrontal regions coactivate with dissociable posterior regions during controlled semantic and phonological tasks

One of the most ubiquitous findings in functional neuroimaging research is activation of left inferior prefrontal cortex (LIPC) during tasks requiring controlled semantic retrieval. Here we show that LIPC participates in the controlled retrieval of nonsemantic representations as well as semantic representations. Results also demonstrate that LIPC coactivates with dissociable posterior regions depending on the information retrieved: activating with left temporal cortex during the controlled retrieval of semantics and with left posterior frontal and parietal cortex during the controlled retrieval of phonology. Correlation of performance to LIPC activation suggests a processing role associated with mapping relatively ambiguous stimulus-to-representation relationships during both semantic and phonological tasks. These findings suggest that LIPC participates in controlled processing across multiple information domains collaborating with dissociable posterior regions depending upon the kind of information retrieved.