We thank our student research assistants and interns for their help with the data collection. We would also like to express our gratitude to our participants. This is a study containing multiple data sets from different laboratories. Results from these datasets were previously published to test different research questions. A list of the publications pertaining to each data set is provided in the Method section of the manuscript.We report how we determined our sample sizes, all exclusions of participants, and all measures as relevant for the research questions. There were no manipulations. Results reported in this manuscript were previously presented as a flash talk at the Annual Conference of the Society for Affective Science 2017 in Boston, MA, USA.

Previous research has shown that individual differences in negative emotion differentiation may play a prominent role in well-being. Yet, many basic questions about negative emotion differentiation remain unanswered, including how it relates and overlaps with related and known dimensions of individual differences and what its possible underlying processes are. To answer these questions, in the current article we present three correlational studies that chart the nomological network of individual differences in negative emotion differentiation in terms of personality, difficulties in identifying and describing feelings, and several indicators of well-being, propose a novel paradigm to assess it in the lab, and explore relationships with a possible underlying mechanism in terms of the motivation to approach or avoid emotions. The results affirm consistent relations between negative emotion differentiation and indicators of adjustment like negative affect, self-esteem, neuroticism, depression and meta-knowledge about one's emotions, and show how it is related to the motivation to experience affective states.

Emotion differentiation, which involves experiencing and labeling emotions in a granular way, has been linked with well-being. It has been theorized that differentiating between emotions facilitates effective emotion regulation, but this link has yet to be comprehensively tested. In two experience-sampling studies, we examined how negative emotion differentiation was related to (a) the selection of emotion-regulation strategies and (b) the effectiveness of these strategies in downregulating negative emotion ( Ns = 200 and 101 participants and 34,660 and 6,282 measurements, respectively). Unexpectedly, we found few relationships between differentiation and the selection of putatively adaptive or maladaptive strategies. Instead, we found interactions between differentiation and strategies in predicting negative emotion. Among low differentiators, all strategies (Study 1) and four of six strategies (Study 2) were more strongly associated with increased negative emotion than they were among high differentiators. This suggests that low differentiation may hinder successful emotion regulation, which in turn supports the idea that effective regulation may underlie differentiation benefits.

Emotion differentiation, the ability to make fine-grained distinctions between emotional states, has mainly been studied as a trait. In this research, we examine within-person fluctuations in emotion differentiation and hypothesize that stress is a central factor in predicting these fluctuations. We predict that experiencing stress will result in lower levels of emotion differentiation. Using data from a 3-wave longitudinal experience sampling study, we examined the within-person fluctuations in the level of emotion differentiation across days and months and tested if these fluctuations related to changes in stress levels. On the day-level, we found that differentiation of negative emotions varied significantly within individuals, that high stress levels were associated with lower levels of emotion differentiation, and that stress on 1 day negatively predicted the level of differentiation of negative emotions on a next day (but not vice versa). On the wave-level, we found a concurrent, but not a prospective relationship between stress and emotion differentiation. These results are the first to directly demonstrate the role of stress in predicting fluctuations in emotion differentiation and have implications for our theoretical understanding of emotion differentiation, as well as for interventions. (PsycINFO Database Record

Increased moment-to-moment predictability, or inertia, of negative affect has been identified as an important dynamic marker of psychological maladjustment, and increased vulnerability to depression in particular. However, little is known about the processes underlying emotional inertia. The current article examines how the emotional context, and people's responses to it, are related to emotional inertia. We investigated how individual differences in the inertia of negative affect (NA) are related to individual differences in exposure, reactivity, and recovery from emotional events, in daily life (assessed using experience sampling) as well as in the lab (assessed using an emotional film-clip task), among 200 participants commencing their first year of tertiary education. This dual-method approach allowed us to assess affective responding on different timescales, and in response to standardized as well as idiographic emotional stimuli. Our most consistent finding, across both methods, was that heightened NA inertia is related to decreased NA recovery following negative stimuli, suggesting that higher levels of inertia may be mostly driven by impairments in affect repair following negative events.