Brandon J. Schmeichel

Self-control relies on glucose as a limited energy source: Willpower is more than a metaphor.

The present work suggests that self-control relies on glucose as a limited energy source. Laboratory tests of self-control (i.e., the Stroop task, thought suppression, emotion regulation, attention control) and of social behaviors (i.e., helping behavior, coping with thoughts of death, stifling prejudice during an interracial interaction) showed that (a) acts of self-control reduced blood glucose levels, (b) low levels of blood glucose after an initial self-control task predicted poor performance on a subsequent self-control task, and (c) initial acts of self-control impaired performance on subsequent self-control tasks, but consuming a glucose drink eliminated these impairments. Self-control requires a certain amount of glucose to operate unimpaired. A single act of self-control causes glucose to drop below optimal levels, thereby impairing subsequent attempts at self-control.

Executive functions and self-regulation

Self-regulation is a core aspect of adaptive human behavior that has been studied, largely in parallel, through the lenses of social and personality psychology as well as cognitive psychology. Here, we argue for more communication between these disciplines and highlight recent research that speaks to their connection. We outline how basic facets of executive functioning (working memory operations, behavioral inhibition, and task-switching) may subserve successful self-regulation. We also argue that temporary reductions in executive functions underlie many of the situational risk factors identified in the social psychological research on self-regulation and review recent evidence that the training of executive functions holds significant potential for improving poor self-regulation in problem populations.

What Is Ego Depletion? Toward a Mechanistic Revision of the Resource Model of Self-Control:

According to the resource model of self-control, overriding one’s predominant response tendencies consumes and temporarily depletes a limited inner resource. Over 100 experiments have lent support to this model of ego depletion by observing that acts of self-control at Time 1 reduce performance on subsequent, seemingly unrelated self-control tasks at Time 2. The time is now ripe, therefore, not only to broaden the scope of the model but to start gaining a precise, mechanistic account of it. Accordingly, in the current article, the authors probe the particular cognitive, affective, and motivational mechanics of self-control and its depletion, asking, “What is ego depletion?” This study proposes a process model of depletion, suggesting that exerting self-control at Time 1 causes temporary shifts in both motivation and attention that undermine self-control at Time 2. The article highlights evidence in support of this model but also highlights where evidence is lacking, thus providing a blueprint for future research. Though the process model of depletion may sacrifice the elegance of the resource metaphor, it paints a more precise picture of ego depletion and suggests several nuanced predictions for future research.

Attention Control, Memory Updating, and Emotion Regulation Temporarily Reduce the Capacity for Executive Control.

This research tested the hypothesis that initial efforts at executive control temporarily undermine subsequent efforts at executive control. Four experiments revealed that controlling the focus of visual attention (Experiment 1), inhibiting predominant writing tendencies (Experiment 2), taking a working memory test (Experiment 3), or exaggerating emotional expressions (Experiment 4) undermined performance on subsequent tests of working memory span, reverse digit span, and response inhibition, respectively. The results supported a limited resource model of executive control and cast doubt on competing accounts based on mood, motivation, or task difficulty. Prior efforts at executive control are a significant contextual determinant of the operation of executive processes.

Self-Affirmation and Self-Control: Affirming Core Values Counteracts Ego Depletion

Research has established that acts of self-control deplete a resource required for subsequent self-control tasks. The present investigation revealed that a psychological intervention-self-affirmation-facilitates self-control when the resource has been depleted. Experiments 1 and 2 found beneficial effects of self-affirmation on self-control in a depleted state. Experiments 3 and 4 suggested that self-affirmation improves self-control by promoting higher levels (vs. lower levels) of mental construal. Self-affirmation therefore holds promise as a mental strategy that reduces the likelihood of self-control failure.

Working Memory Capacity and the Self-Regulation of Emotional Expression and Experience

This research examined the relationship between individual differences in working memory capacity and the self-regulation of emotional expression and emotional experience. Four studies revealed that people higher in working memory capacity suppressed expressions of negative emotion (Study 1) and positive emotion (Study 2) better than did people lower in working memory capacity. Furthermore, compared to people lower in working memory capacity, people higher in capacity more capably appraised emotional stimuli in an unemotional manner and thereby experienced (Studies 3 and 4) and expressed (Study 4) less emotion in response to those stimuli. These findings indicate that cognitive ability contributes to the control of emotional responding.

Self-regulatory processes defend against the threat of death : Effects of self-control depletion and trait self-control on thoughts and fears of dying

Nine studies (N = 979) demonstrated that managing the threat of death requires self-regulation. Both trait and state self-control ability moderated the degree to which people experienced death-related thought and anxiety. Participants high (vs. low) in self-control generated fewer death-related thoughts after being primed with death, reported less death anxiety, were less likely to perceive death-related themes in ambiguous scenes, and reacted with less worldview defense when mortality was made salient. Further, coping with thoughts of death led to self-regulatory fatigue. After writing about death versus a control topic, participants performed worse on several measures of self-regulation that were irrelevant to death. These results suggest that self-regulation is a key intrapsychic mechanism for alleviating troublesome thoughts and feelings about mortality.

Self-Affirmation and Mortality Salience: Affirming Values Reduces Worldview Defense and Death-Thought Accessibility:

To the extent that cultural worldviews provide meaning in the face of existential concerns, specifically the inevitability of death, affirming a valued aspect of one’s worldview should render reminders of death less threatening. The authors report two studies in support of this view. In Study 1, mortality salience led to derogation of a worldview violator unless participants had first affirmed an important value. In Study 2, self-affirmation before a reminder of death was associated with reduced accessibility of death-related thoughts a short while thereafter. The authors propose that actively affirming one’s worldview alters reactions to reminders of mortality by reducing the accessibility of death-related thoughts, not by boosting self-esteem. These studies attest to the flexible nature of psychological self-defense and to the central role of cultural worldviews in managing death-related concerns.

Terror Management Theory and Self-Esteem Revisited: The Roles of Implicit and Explicit Self-Esteem in Mortality Salience Effects

Three studies tested the roles of implicit and/or explicit self-esteem in reactions to mortality salience. In Study 1, writing about death versus a control topic increased worldview defense among participants low in implicit self-esteem but not among those high in implicit self-esteem. In Study 2, a manipulation to boost implicit self-esteem reduced the effect of mortality salience on worldview defense. In Study 3, mortality salience increased the endorsement of positive personality descriptions but only among participants with the combination of low implicit and high explicit self-esteem. These findings indicate that high implicit self-esteem confers resilience against the psychological threat of death, and therefore the findings provide direct support for a fundamental tenet of terror management theory regarding the anxiety-buffering role of self-esteem.

Mortality Salience Increases Adherence to Salient Norms and Values

Four studies indicate that mortality salience increases adherence to social norms and values, but only when cultural norms and values are salient. In Study 1, mortality salience coupled with a reminder about cultural values of egalitarianism reduced prejudice toward Blacks among non-Black participants. In Studies 2 through 4, a mortality salience induction (e.g., walking through a cemetery) increased self-reported and actual helping behavior only when the cultural value of helping was salient. These results suggest that people may adhere to norms and values so as to manage awareness of death.