5. A comparative perspective on executive and motivational control by the medial prefrontal cortex

Overview The goal of this chapter is to describe recent efforts at understanding the functional significance of " prefrontal " areas in the cerebral cortex of rodents with regard to cognitive and motivational control. Previous discussions on the comparative anatomy of the prefrontal cortex have been framed around the question " Do rats have prefrontal cortex? " 46, 61. Researchers using rodents then tried to make the case that medial parts of the rodent frontal cortex are homologous to dorsolateral (granular) parts of frontal cortex that exist in primates 61. Later, interest developed in medial regions of the prefrontal cortex and, despite never being resolved, the discussion about the precise nature of rodent prefrontal cortex seemed to go away. I would like to reexamine this issue, but from a different perspective. Rather than asking if rats have prefrontal cortex, I would like to ask – to borrow a phrase from Jon Kaas 24 – " What, if anything, is rodent prefrontal cortex? " In this chapter, I try to answer this question based on studies of the anatomical connectivity between the medial prefrontal cortex (mPFC) and the hypothalamus, and on recent studies on mPFC during performance of simple reaction-time tasks. Together, these studies suggest that medial prefrontal regions have a privileged role in controlling the autonomic nervous system and thereby contribute at a most visceral level to cognitive and motivational control. A neural circuit model is proposed for the generation of persistent neural