Degree of automaticity and the prefrontal cortex

• Degree of automaticity may be critical in the functional organization of the PFC.
• Posterior-to-anterior gradient system is represented for low degree of automaticity.
• Posterior-confined system is involved in high degree of automaticity.
• This renders broad generalizations to cognitive processes in various domains.

The dorsolateral prefrontal cortex (PFC), with more anterior areas [Brodmann area (BA) 45, 47, and 10], has been known to be activated as cognitive hierarchy increases. However, this does not hold for highly automatic processes such as first language (L1), where the posterior region (BA 44) is known as the key area for the processing of complex linguistic hierarchy. Discussing this disparity, we propose that the degree of automaticity (DoA) is a crucial factor for the framework of functional mapping in the PFC: the posterior-to-anterior gradient system for more controlled processes and the posterior-confined system for automatic processes. We support this view with previous findings and provide a new perspective on the functional organization of the PFC.