Self-regulation is a key component to success in multiple contexts. Nevertheless, people often fail to exert self-control. The present entry discusses one theoretical account self-regulation failures: the ego-depletion model of self-control. The entry summarizes the area of ego depletion by first examining two models of ego depletion – the resource model and the process model – and then discussing the role of individual differences in the ego-depletion process.
Ego Depletion: Definition, Theoretical Models, and the Role of Individual Differences
Forty-one percent of Americans make New Year’s resolutions each year; however, only about 9% report that they were successful in achieving their resolution by the end of the year (New Year’s Resolution Statistics 2017). Why do 81% of people fail to keep their New Year’s resolutions? For many, the cause is a failure of self-regulation – the ability to engage self-control to resist immediate temptation in pursuit of long-term ambitions and interests (Baumeister and Vohs 2007). Self-regulation is a key component to success in multiple contexts including school, workplaces, relationships, physical health, and mental well-being. Nevertheless, people often fail to exert self-control. The present entry discusses one theoretical account self-regulation failures: the ego-depletion model of self-control.
Research suggests that self-regulation becomes less effective after continuous use – a process called ego depletion (Baumeister and Vohs 2007). Since the early 2000s, researchers have investigated ego-depletion effects in a variety of different contexts and types of people (see Hagger et al. 2010; Inzlicht and Schmeichel 2012, for reviews). The present entry aims to summarize the area of ego depletion by first examining two models of ego depletion – the resource model and the process model – and then discussing the role of individual differences in the ego-depletion process.
The Resource Model of Ego Depletion
The first and perhaps most prominent account of ego depletion is the resource model of self-control. The resource model suggests that self-control relies on a limited resource that becomes depleted as self-control is exerted (see Baumeister and Vohs 2007; Hagger et al. 2010 for a review). In other words, self-control functions similarly to a muscle: becoming fatigued and unusable with continued exertion. Most of the work on the resource model of self-control comes from experimental social psychology. In a typical experiment, researchers ask participants to work on two consecutive tasks. For half of participants – those in ego-depletion condition – the two consecutive tasks require self-control (e.g., resisting tempting foods, suppressing emotions, completing effortful cognitive tasks, squeezing a handgrip). For the other half of participants – those in the control condition – only the second task requires self-control. Researchers assume ego depletion when participants in the ego-depletion condition perform worse on the second task relative to participants in the control condition. Resource model theorists argue that engaging in the initial self-regulation task depletes people’s self-regulation stores and thus impairs performance on the second task.
Additional support for the resource model comes from evidence that people can employ a number of strategies to attenuate the influence of ego depletion (see Hagger et al. 2010 for a review). First, just as exercising a muscle improves its strength, people who practice self-control are less susceptible to ego-depletion manipulations. For example, participants in one study either practiced or did not practice self-control exercises (i.e., monitoring posture, regulating mood, monitoring eating) for 2 weeks. Subsequently, when they completed a classic ego-depletion study in the lab, those who had practiced self-control over the prior 2 weeks showed less susceptibility to ego depletion – persisting longer on a handgrip task – than did those who had not practiced self-control. Additionally, just as distance runners preserve their energy to clock their fastest times at the end of a race, people who anticipate engaging in future self-control strategically conserve their self-regulatory resources to best prepare for the future demands. Finally, just as resting a muscle can restore its strength, people who rest after self-regulating perform better on consecutive self-control task.
The Process Model of Ego Depletion
Despite hundreds of studies providing evidence for resource model of self-control, some researchers have recently questioned the validity of the model including a recent failure to replicate the ego-depletion effects in large-scale registered replication (Hagger and Chatzisarantis 2016). Emerging from these criticisms is the more recent process model of ego depletion, which suggests that self-regulation failures result in shifts in motivation and attention rather than depletion of limited stores of self-control ability (Inzlicht and Schmeichel 2012). The process model of ego depletion argues that after engaging in self-control, people’s motivation and attention to subsequent self-control efforts decrease, while their motivation and attention to impulses and temptations increase. Thus, the process model does not view ego depletion as a result of lost resources but instead as a result of low motivation for and attention to self-regulatory goals.
Support for the process model comes from two primary sources. Supporting a motivational component of self-control is evidence that external incentives for self-regulation (e.g., money) can eliminate ego-depletion effects altogether (Muraven and Slessareva 2003), Supporting an attentional component of self-control is neural evidence that self-regulatory tasks reduce activation of the anterior cingulate cortex – the neural system responsible for attending to goal progress (Inzlicht and Gutsell 2007). The resource model struggles to account for these findings, suggesting that the process model might provide a better, though less pithy, account of ego-depletion findings.
Individual Difference Moderators
Important to understanding the nature of ego depletion are the individual differences that contribute to and moderate experimental ego-depletion effects (see Hagger et al. 2010; Inzlicht and Schmeichel 2012, for reviews). Research suggests a variety of individual differences important to ego depletion, which fall into two broad categories: (1) self-control tendencies and (2) self-control mind-sets.
Self-control tendencies. People high in trait self-control abilities – those who regularly excel at self-regulation – appear to be less susceptible to ego depletion. For instance, in one study, people high in self-control motivation gambled less often than did those with low self-control motivation after depletion (Schmeichel et al. 2010). Similarly, traits that indicate that people regularly engage in self-control also relate to people’s apparent immunity to ego depletion. For instance, those who are high in self-monitoring – attending to and regulating one’s behavior to match the social situation – are less susceptible to ego depletion. Additionally, people high in trait consideration of future consequences – those who attend to and peruse long-term goals – are less susceptible to ego depletion. Finally, people high in fluid intelligence – an ability related to executive functioning and self-regulation – are also less susceptible to depletion (Shamosh and Gray 2007).
Self-control mind-sets. Individual differences in beliefs about willpower also moderate ego depletion. Compared to people who believe willpower is a finite resource, those who believe that willpower is an unlimited resource perform better on a self-regulatory task (i.e., a Stroop task) after being depleted. Relatedly, research suggests that believing a task depletes self-regulatory stores is more important than actually completing a depleting task in creating ego-depletion effects (Clarkson et al. 2010).
Engaging in sustained self-control remains one of people’s most difficult challenges. The onset of this chapter referenced the low success rate for sticking by New Year’s resolutions. Although people become disheartened at their resolution failures, research on ego depletion suggests that it is often difficult for people to maintain self-control over a short experimental session, let alone an entire year. To date, the resource and process models of ego depletion remain compelling explanations for failures of self-control. Most relevant to this handbook, some types of people (e.g., those whose traits cause them to engage in regular self-control) are more inclined to sustain self-control despite depletion. Nevertheless, the majority of research on and theorizing surrounding ego depletion has focused on situations that induce ego depletion. Needed is a more robust body of work pinpointing the importance of individual differences in ego depletion.
- New Year’s Resolution Statistics. (2017). Statistic Brain Research Institute. Retrieved from http://www.statisticbrain.com/new-years-resolution-statistics/.