The circadian neurobiology of reward

Circadian clocks are important regulators of physiology and behavior. In the brain, circadian clocks have been described in many centers of the central reward system. They affect neurotransmitter signaling, neuroendocrine circuits, and the sensitivity to external stimulation. Circadian disruption affects reward signaling, promoting the development of behavioral and substance use disorders. In this review, we summarize our current knowledge of circadian clock-reward crosstalk. We show how chronodisruption affects reward signaling in different animal models. We then translate these findings to circadian aspects of human reward (dys-) function and its clinical implications. Finally, we devise approaches to and challenges in implementing the concepts of circadian medicine in the therapy of substance use disorders.

Automated summary

Circadian clocks play a crucial role in regulating physiology and behavior, particularly in the central reward system. They impact neurotransmitter signaling, neuroendocrine circuits, and sensitivity to external stimuli. Disruption of circadian rhythms can affect reward signaling, leading to the development of behavioral and substance use disorders. This review summarizes current knowledge on the interaction between circadian clocks and reward, highlighting the effects of chronodisruption on reward signaling in animal models. The translation of these findings to human reward (dys-) function and the clinical implications are discussed, along with the challenges and approaches in incorporating circadian medicine concepts into the therapy of substance use disorders.