Orexin Neurons Gate Sustained Motivation, Study Finds

Nagoya University researchers show orexin neurons are a necessary gate for sustained, goal-directed effort: their activity scales with the required effort, suppression lowers motivation, and boosting activity beyond natural levels does not increase motivation. Using a novel orexin-Cre rat model, chemogenetics raised breakpoints on progressive-ratio tasks while fiber photometry showed anticipation-linked orexin activity that intensifies with effort; optogenetic inhibition reduced motivation, but excitation beyond baseline did not boost it. The findings illuminate how reward prediction drives action and suggest targets for motivational deficits in mental illness, with future work on the surrounding circuitry.