In addition to the lateral temporo-prefrontal areas, theta estimated to the ACC was greater to SW than to PW under placebo. As discussed in greater detail below, the ACC contributes to a variety of tasks that require monitoring of potential conflict. The present results along with other evidence, suggest that it is also involved in semantic processing across sensory modalities (Marinkovic et al., 2003). A functional connectivity study (Stamatakis et al., 2005) showed that the ACC modulated the interactions between the left IPF and middle temporal gyrus during processing of words that differed in the inflection regularity. Concurrent engagement of the temporo–fronto–cingulate network seems to indicate that the semantic retrieval in the context of an executive task is subserved by a distributed system (Gold and Buckner, 2002; Noppeney et al., 2004; Binder et al., 2009). Relative contributions of these areas depend on task parameters such as difficulty, depth of semantic processing, and semantic retrieval relies upon memory search, selection, response selection, and execution.
