The Functional Organization of the Prefrontal Cortex
The PFC comprises multiple distinct sub-regions including the ventrolateral (VLPFC), dorsolateral (DLPFC), and rostrolateral (RLPFC) sectors. While considerable empirical work suggests that these sub-regions support distinct processes, a coherent theory of the functional organization of the PFC has remained elusive. This line of research is aimed at discerning this functional organization. We have found evidence for a rostro-to-caudal gradient of abstraction in the representations supported by the PFC, with concrete, moderately abstract, and highly abstract information being supported by the VLPFC, DLPFC, and RLPFC respectively (Christoff, Keramatian, Gordon, Smith, and Maedler, 2009). This study complemented a review of episodic memory, working memory, reasoning, and multitasking studies suggesting a hierarchical organization of lateral PFC regions (Christoff & Gabrieli, 2000). Our latest work in this area has provided further evidence for rostro-caudal (i.e., anterior-posterior) functional hierarchies in prefrontal brain regions, according to how abstract the information being processed is (Dixon, Fox, and Christoff, submitted).