A neurocomputational model of human frontopolar cortex function

The frontopolar cortex (FPC), the most anterior part of the lateral prefrontal cortex corresponding to Brodmanns area 10, is involved in human high-order cognition, including reasoning, problem-solving and multitasking. Its specific contribution to prefrontal executive function, however, remains unclear. A neurocomputational model suggests that the FPC implements a basic process referred to as cognitive branching that maintains a task in a pending state during the execution of another, and enables to revert back to it upon completion of the ongoing one. However, the FPC is engaged in other cognitive functions including prospective memory, relational reasoning, episodic memory retrieval and attentional set-shifting, which are not directly linked to the notion of cognitive branching. Here we used a neurocomputional branching model to simulate the involvement of the FPC in these various cognitive functions. Simulation results indicate that the model accounts for the variety of FPC activations observed in these various experimental paradigms. Thus, the present study provides theoretical evidence suggesting that all these behavioral paradigms implicitly involve branching processes, and supports the idea that cognitive branching is the core function of the human frontopolar cortex.