Complex functions of human lateral frontopolar cortex

Recent anatomical studies have shown that, compared to other primates, the human frontal pole (FP) contains a unique lateral subdivision (FPl). This area provides an important target for understanding the uniqueness of human intelligence. Paradoxically, patients with FP lesions often perform normally on standard neuropsychological tests, while experiencing problems in real-life or simulated situations. This paper aims to review the complex functions of the FPl that may account for the dysfunctions observed in these patients. First, we consider studies of FP lesion patients that reveal deficits in analogical reasoning and prospective memory. Second, we review, mainly based on neuroimaging and neurostimulation studies, the FPl's involvement in exploratory decision making, information integration and the representation of abstract rules. We argue that these functions primarily stem from the FPl's capacity to manage multiple sources of information and to reduce that information into simpler features for guiding behaviour. Finally, we propose a model of the FPl that emphasizes its role in decomposing high-dimensional information to enhance decision making processes in conjunction with connected regions, including the posterior cingulate cortex, anterior cingulate cortex, and dorsolateral prefrontal cortex.