How do the basal ganglia regulate sleep–wake behavior?

The basal ganglia (BG) are involved in motor function, habit formation, and reward or addictive behaviors, but the question as to how the BG integrate arousal with these fundamental striatal functions has only recently received much attention. Findings based on electrophysiology, neurotoxic lesioning, and the use of transgenic animals have established that the striatum and globus pallidus are key structural elements for the control of sleep and wakefulness. Here, we discuss emerging anatomical and molecular mechanisms of sleep–wake regulation at work in the BG. Furthermore, we propose a model whereby adenosine and dopamine receptors in the nucleus accumbens (NAc) are involved in the integration of behavioral processes and the induction of wakefulness through cortical activation.