The Limited Resource theory of self-control (47) posits that individuals have a finite reserve of self-control that they can employ to regulate their behavior. If demands on self-control are excessive and/or maintained over a long period of time then this resource will become depleted and subsequent attempts to regulate behavior will be unsuccessful; the state of having depleted self-control resources has been termed “Ego Depletion.” The analogy of self-control as a muscle is often used: in the same way that repeated exertion of a muscle over a short period of time will weaken that muscle and lead to fatigue, self-control capacity will be diminished after exerting self-control for a prolonged period (47, 48). In relation to substance use, individuals may need to engage self-control in order to overcome urges or cravings to use the substance when they encounter substance-related cues. For example, Muraven and Shmueli (49) found that when social drinkers were exposed to alcohol cues, they showed greater disinhibition than when exposed to neutral cues. A similar pattern of results was reported by Gauggel et al. (50) in detoxified
