The central governor model suggests that exertion is throttled by some central nervous system mechanism that receives information about energetic bodily needs and motivational drives to regulate exertion and, ultimately, to prevent homeostatic breakdown, chiefly energy depletion. ¹ The central governor is proposed to be some central nervous system mechanism that takes as input information about energetic needs, current physiological states, and various motivational drives to regulate physical exertion to save the organism from catastrophic homeostatic failures during physical exertion.²

The model offers a plausible ultimate explanation for why self-control seems to wane over time. Without a central governor that throttles physical effort, people might exert themselves to the point of hurting themselves and causing serious bodily damage. No bodily harm is caused by mental exertion, but the same throttle mechanism is thought to be at work. ¹