In experiments with rats, activity in orexin neurons rose as the animals anticipated food and worked harder to receive it. The team first activated orexin neurons using chemogenetics. Animals whose orexin neurons had been selectively degenerated stopped sooner and recorded lower breakpoints. Suppressing orexin neurons weakens motivation, but overstimulation adds no boost ©ShutterstockThat difference was one of the study’s main findings. Future research will examine the brain circuits that send information to orexin neurons and receive signals from them.