Katharina Bernecker

Beliefs about willpower determine the impact of glucose on self-control

Significance The present research provides critical new findings about the role of glucose ingestion in self-control and cognitive performance. It argues against the popular view that self-control depends on a limited physiological resource (blood glucose) that is depleted by even brief acts of self-control and is restored by glucose consumption. Instead, the results highlight the critical role of beliefs about willpower in self-control performance. Past research found that the ingestion of glucose can enhance self-control. It has been widely assumed that basic physiological processes underlie this effect. We hypothesized that the effect of glucose also depends on people’s theories about willpower. Three experiments, both measuring (experiment 1) and manipulating (experiments 2 and 3) theories about willpower, showed that, following a demanding task, only people who view willpower as limited and easily depleted (a limited resource theory) exhibited improved self-control after sugar consumption. In contrast, people who view willpower as plentiful (a nonlimited resource theory) showed no benefits from glucose—they exhibited high levels of self-control performance with or without sugar boosts. Additionally, creating beliefs about glucose ingestion (experiment 3) did not have the same effect as ingesting glucose for those with a limited resource theory. We suggest that the belief that willpower is limited sensitizes people to cues about their available resources including physiological cues, making them dependent on glucose boosts for high self-control performance.

Are Implicit Motives the Need to Feel Certain Affect? Motive–Affect Congruence Predicts Relationship Satisfaction

The authors test the assumption that the core of implicit motives is the desire for particular affective experiences and that motive satisfaction need not be tied to any particular domain. Using the context of romantic relationships, cross-sectional Study 1 and experimental Study 2 showed that people with a high affiliation motive were more satisfied when they experienced more affiliation-specific affect (calmness and relaxation). However, people with a higher power motive were more satisfied in their relationships when they experienced more power-specific affect (strength and excitement) in these relationships. The results support the idea that an implicit motive involves the desire for specific affective experiences and that frequent experiences of one’s preferred affect can lead to enhanced satisfaction and well-being in a domain, even one that is not typically associated with that motive.

Beliefs about willpower moderate the effect of previous day demands on next day's expectations and effective goal striving.

Research suggests that beliefs about willpower affect self-regulation following previous self-regulatory demands (Job et al., 2010). Some people believe that their willpower is limited, meaning that after a demanding task it needs to be replenished (limited theory). By contrast, others believe that willpower is not limited and that previous self-control tasks even activate willpower (non-limited theory). We hypothesized that when people experience a demanding day their beliefs about willpower predict their expected capacity to self-regulate and their actual self-regulation on the following day. In a daily diary study (N = 157), we measured students’ daily level of demands, their expected performance in unpleasant tasks, and their effective goal striving. Results showed that following a demanding day, students with a non-limited theory had higher expectations about their progress in unpleasant tasks and were striving more efficiently for their goals than students with a limited theory. These findings suggest that beliefs about willpower affect whether demands experienced on a previous day have positive or negative consequences on people’s self-regulation.

Beliefs About Willpower Are Related to Therapy Adherence and Psychological Adjustment in Patients With Type 2 Diabetes

Research suggests that self-control, the ability to forego immediate needs for the sake of future rewards, promotes health behavior. The present study examined the role of beliefs about willpower as predictor of self-control in the context of diabetes. Seventy-nine type 2 diabetes patients reported their beliefs about willpower, therapy adherence (i.e., self-care activities, diet, exercise), and psychological adjustment (i.e., emotional distress, well-being, life quality). Endorsing the belief that willpower is a limited versus nonlimited resource was associated with lower therapy adherence and lower psychological adjustment. How people think about their willpower might be crucial for therapy success in diabetes patients.

The Process of Disengagement From Personal Goals

To date, it is not well understood how individuals disengage from goals. A recent approach suggests that disengagement is often preceded by an action crisis, a motivational conflict in which the individual is torn between holding on to and letting go of a personal goal. We postulate that a dynamic interplay between the experience of action crisis and appraisals of goal desirability and attainability shapes the disengagement process from personal goals. In two longitudinal studies (N = 364), an action crisis in the goal to complete a university degree predicted devaluations of its desirability and attainability, and reversely, low goal attainability (but not desirability) predicted an increase in action crisis. Moreover, studies provided first evidence that devaluing goal desirability might be functional for well-being in an action crisis. Studies strengthen the view that disengagement is shaped by reciprocal processes between the experience of action crisis and changes in goal appraisal.

Implicit Theories About Willpower in Resisting Temptations and Emotion Control

Previous research suggests that people’s implicit theories about willpower affect continuous self-control performance in the domain of strenuous mental activities. The present research expands these findings to two further domains of self-control: resisting temptations and emotion control. In Study 1, participants were either led to resist a temptation or not. Participants who believed that willpower gets depleted by resistance to temptations (limited-resource theory) performed significantly worse in a subsequent Stroop task compared to participants who believed that resisting temptations activates their willpower (nonlimited-resource theory). In Study 2, participants controlled their emotions during a funny video or were allowed to express them. Participants who believed that controlling emotions depletes willpower performed worse in a subsequent persistence task than those who believed that controlling emotions activates willpower. Results suggest that implicit theories about willpower are domain specific and sensitive to the domain of the initial self-control task rather than that of the subsequent self-control task.

Temporal dynamics of couples’ communication behaviors in conflict discussions: A longitudinal analysis

Negative and positive conflict communication predicts long-term relationship satisfaction. However, some studies show harmful effects and others show beneficial effects of negative conflict communication on long-term relationship satisfaction. One reason for the heterogeneous results might be that most studies focused on aggregated behaviors across a conflict interaction but neglected the temporal dynamics within such an interaction. This study examined whether individual initial levels and temporal trajectories of negative and positive communications predict long-term relationship satisfaction, and whether self-efficacy beliefs about clarity of other’s feelings (CoF) alter initial levels and temporal trajectories of negative and positive communications. Negative and positive communications were measured based on sequentially coded conflict discussions of 365 couples; self-efficacy beliefs about CoF and relationship satisfaction were measured by self-report questionnaires at baseline and at four annual follow-up assessments. Results revealed that women’s initial positive communication predicted higher intercepts of both partners’ relationship satisfaction, and stronger decreases in women’s negative communication predicted a higher intercept of relationship satisfaction in women. Additionally, less steep decreases in women’s trajectories of negative communication predicted greater maintenance in women’s relationship satisfaction over time. Additionally, men’s self-efficacy beliefs about CoF predicted decreases in men’s negative communication, increases in women’s negative communication, and higher initial levels of women’s positive communication. The current study highlights the relevance of dynamic aspects of partners’ communication behaviors.