Hierarchical reinforcement learning and decision making.

The hierarchical structure of human and animal behavior has been of critical interest in neuroscience for many years. Yet understanding the neural processes that give rise to such structure remains an open challenge. In recent research, a new perspective on hierarchical behavior has begun to take shape, inspired by ideas from machine learning, and in particular the framework of hierarchical reinforcement learning. Hierarchical reinforcement learning builds on traditional reinforcement learning mechanisms, extending them to accommodate temporally extended behaviors or subroutines. The resulting computational paradigm has begun to influence both theoretical and empirical work in neuroscience, conceptually aligning the study of hierarchical behavior with research on other aspects of learning and decision making, and giving rise to some thought-provoking new findings.