Neural Representations Used to Specify Action

To understand how we use rules to guide our behavior, it is critical to learn more about how we select responses on the basis of associations retrieved from long-term memory and held online in working memory. Rules, or prescribed guide(s) for conduct or action (Merriam-Webster Dictionary, 1974), are a particularly interesting class of associations because they link memory and action. We previously reviewed the cognitive neuroscience of rule representations elsewhere (Bunge, 2004; Bunge et al., 2005). In this chapter, we focus mainly on recent functional brain imaging studies from our laboratory exploring the neural substrates of rule storage, retrieval, and maintenance. We present evidence that goal-relevant knowledge associated with visual cues is stored in the posterior middle temporal lobe. We further show that ventrolateral prefrontal cortex (VLPFC) is engaged in the effortful retrieval of rule meanings from longterm memory as well as in the selection between active rule meanings. Finally, we provide evidence that different brain structures are recruited, depending on the type of rule being represented, although VLPFC plays a general role in rule representation. Although this chapter focuses primarily on the roles of lateral prefrontal and temporal cortices in rule representation, findings in parietal and premotor cortices will also be discussed.