Evolutionary Perspectives: Homologies and Analogies

Excerpt

Determining homologies and analogies of brain structure and function across species is of major interest in systems neuroscience, comparative biology, and brain mapping. Prefrontal cortex (PFC) is a continued target of such analyses because it has expanded considerably throughout evolution. It is heavily differentiated and expanded in primates compared to mouse, rat, tree shrew, and marmoset brains, and it performs computational functions that are more complex than other association cortex.

This chapter reviews the major regions and circuits observed across species within PFC. It looks at the evolution of PFC and how this could produce higher-order cognition, including social behavior, as well as language elements in humans. It provides a synopsis of some main organizational principles of PFC as well as potential mechanisms by which major circuits in PFC exert control. It then reviews how unique contributions of optogenetics, chemogenetics, large-scale electrophysiology, and calcium imaging contribute to understanding PFC function. It also addresses the utility of animal models for understanding the structure and function of PFC.

The discussions that contributed to this chapter provide a modern foundation for the ongoing goal of generating a consensus statement regarding the ambition of determining the homologies and analogies of PFC, as well as the cognitive, developmental, and translational insights gleaned from the promise of such an eventual consensus statement.