Switching from automatic to controlled behavior: cortico-basal ganglia mechanisms.

Most daily tasks are performed almost automatically, but occasionally it is necessary to alter a routine if something changes in the environment and the routine behavior becomes inappropriate. Such behavioral switching can occur either retroactively based on error feedback or proactively by detecting a contextual cue. Recent imaging and electrophysiological data in humans and monkeys support the view that the frontal cortical areas play executive roles in behavioral switching. The anterior cingulate cortex acts retroactively and the pre-supplementary motor area acts proactively to enable behavioral switching. The lateral prefrontal cortex reconfigures cognitive processes constituting the switched behavior. The subthalamic nucleus and the striatum in the basal ganglia mediate these cortical signals to achieve behavioral switching. We discuss how breaking a routine to allow more adaptive behavior requires a fine-tuned recruitment of the frontal cortical-basal ganglia neural network.