The prefrontal cortex (PFC) is the most anterior portion of the frontal lobe and the brain region most associated with uniquely human cognitive abilities: planning, decision-making, working memory, cognitive control, personality, and social behavior. It is the last cortical region to mature (reaching full development only in the mid-20s) and the most expanded region in human evolution relative to other primates.
Subdivisions and Functions
The dorsolateral PFC (DLPFC) supports working memory maintenance, cognitive flexibility, and abstract reasoning. The ventrolateral PFC (VLPFC) is involved in semantic retrieval and inhibitory control. The orbitofrontal cortex (OFC) processes reward value and contributes to decision-making and emotion regulation. The medial PFC supports self-referential processing, theory of mind, and default mode network activity. The anterior cingulate cortex (ACC), on the medial surface, monitors for cognitive conflict and signals the need for increased control.
The Case of Phineas Gage
Phineas Gage (1848), who survived an iron rod passing through his frontal lobe, provided early evidence linking the PFC to personality and social behavior. After the injury, Gage's intellectual abilities were reportedly preserved, but his personality changed dramatically — he became impulsive, irresponsible, and socially inappropriate. Modern analysis suggests the damage affected the OFC and ventromedial PFC, consistent with these regions' roles in decision-making and social behavior.
Miller and Cohen's (2001) influential theory proposes that the PFC provides top-down biasing signals that guide activity in other brain regions in accordance with current goals. When you resist a tempting dessert, maintain focus on a boring task, or switch from one activity to another, the PFC sends signals that enhance goal-relevant processing and suppress goal-irrelevant processing throughout the cortex. This biasing function makes the PFC essential for virtually all forms of goal-directed behavior.