The aging process is often coupled with major life changes such as retirement, death of friends and family members, and declines in physical and psychological functioning. Intuitively, any one or a conjunction of these events might be expected to lead to decreases in positive affect (PA) and increases in negative affect (NA). However, older adults tend to be emotionally positive and stable even late in life. Thus, it is possible that emotion-based strategies for coping with the challenges presented in later life can be used effectively by older adults, even amidst potential vulnerabilities in other domains. The design of effective interventions and technologies aimed at facilitating this coping process, will depend on understanding that emotions can influence health in different ways. Affect level and intraindividual variability (IIV) are independently related to distal factors such as personality and health-related outcomes such as immune functioning and mortality, among others. By nature, emotions are subject to daily fluctuations that cannot be captured by investigation of mean affect levels alone. Research on affect IIV has focused primarily on whether there are stability differences in younger and older adults. In general, older adults tend to be more stable, perhaps because the failure to regulate emotions is particularly detrimental for older adults’ physiological health. It is therefore important to understand how proximal factors in everyday life lead to intraindividual emotional changes. The primary goal of this study was to identify the factors occurring within older adults’ daily lives that predicted emotional deviations and to determine whether individuals differed in the types of factors that were emotionally-relevant. As such, it was imperative to employ a methodology that could differentiate the factors that evoked consistent emotional responses across all individuals from the factors whose impact on affect were person-dependent. Specifically, participants were given online surveys three times per day for 20 consecutive weekdays that included assessments of their current positive and negative emotional states and questions (at least once per day) about their stress, pain, sleep quality, life space, physical activity, and social activity. Multilevel modeling (MLM) was used to determine if there was significant affect IIV for these older adults and how much IIV could be explained by these proximal predictors. This analysis approach was used because it is well-suited for nested data (in this case, observations nested within-persons) and does not assume independence of observations (which is a concern when individuals receive repeated assessments). Additionally, MLM analyzes the complete dataset rather than complete cases (individuals), which allowed for comparison of fixed effects regression models and random effects regression models. Random effects models, which are the hallmark of MLM, enabled the analysis of potential individual differences in the within-person relationships between the predictors and affect. As expected, there was significant affect IIV in these older adults for both PA and NA. The predictors of PA and NA were analyzed first in isolation (referred to as “isolated models”) and then when controlling for the other proximal variables (referred to as “full models”). The random effects isolated models were generally better fitting than the fixed effects isolated models, indicating that the models that did not constrain individual predictor-affect slopes to be the same across persons (random) were more accurate representations of the observed data than models that constrained individuals’ slopes to be the same (fixed). Full fixed slopes and full random slopes models were built in stepwise fashion based on the results of the isolated models. Again, the random effects full models better fit the observed data than the fixed effects models for both PA and NA, providing strong evidence in favor of the hypothesis that a larger percentage of affect IIV would be explained when allowing individual differences in the within-person predictor-affect relationships. The full random models accounted for 32% of the PA IIV, and 45% of the NA IIV. These were both better fitting than their respective null models, indicating that overall, the proximal predictors accounted for significant proportions of the within-person PA and NA variance. Certain factors accounted for larger percentages of the IIV than others and in general, there were differences between the PA and NA model in terms of which factors led to emotional fluctuations. Subjective health accounted for the largest percentage of PA IIV and stress accounted for the largest percentage of NA IIV. Additionally, subjective health, life space, stress, and pain were significant unique predictors of PA, NA, or both. However, there were specific unique effects across both PA and NA, namely, the slope variances for stress and pain. Follow-up analyses were unable to account for these slope variances using person-level predictors. In essence, an individual’s emotional reactivity to pain and stress did not depend on his or her overall mean level of those factors, or of the other daily predictors. This provided further evidence that PA and NA should be treated as separable variables (e.g., it is possible for a daily event to decrease older adult’s positivity without necessarily increasing their negativity) but also highlighted factors that have pervasive influences on emotion regardless of valence, which is harmonious with models of affect that propose a dynamic relationship between PA and NA. The results from this study have theoretical and practical implications. Theories on emotional stability often focus on if and why older adults are more stable than younger adults. Findings of the present study both support and expand upon these theories by identifying within an older adult population, which proximal factors were likely to cause emotional deviations after partialling out the effects of other daily variables, including factors that were previously unstudied in this domain. The analysis methodology implemented in the present research allowed for direct investigation of whether certain individuals were more prone to the influences of these factors than others. These results are discussed in the context of coping and resiliency theories that posit individual differences in emotional responses to stimuli based on these capabilities. From a practical perspective, these results highlight that the design of interventions and technologies intended to provide older adults with effective skills and resources to maintain or improve their emotional well-being should be tailored to individuals’ affective profiles.

Ausgehend von der Selbstbestimmungstheorie wird in der Dissertation angenommen, dass bestimmte Merkmale des Unterrichts das Autonomieerleben von Schülern und Schülerinnen positiv oder negativ beeinflussen. Hypothese: Autonomiefördernder Unterricht erhöht das Interesse und die erlebte Kompetenz. Ausgehend von einem dynamischen Verständnis von Unterrichtskontexten, wird der Einfluss von Lernsituation und individuellen motivationalen Ressourcen auf das Motivationserleben der Lernenden in einem intraindividuellen Ansatz untersucht. Unterrichtserleben und Motivation von Schülern und Schülerinnen wurden in einem Prä-Post-Design über den Zeitraum eines Jahres untersucht. Kernstück ist eine 3-wöchige Erhebungsphase, in der Unterrichtserleben und Motivation täglich für drei Fächer erfasst wurden. Manuskript I der Dissertation basiert auf der Interessenstheorie und zeigt den differenziellen Einfluss von stabilem individuellen Interesse und variablen Unterrichtsmerkmalen auf das Erleben von Interesse im Unterricht. Manuskript II zeigt, dass das fachspezifische Selbstkonzept und die wahrgenommenen Unterrichtsmerkmale das Kompetenzerleben der Schüler beeinflussen. Die Autonomieunterstützung im Unterricht hat über das die Autonomie fördernde Klima und Kontrollverhalten der Lehrkraft hinaus einen Effekt auf das Kompetenzerleben der Schüler und Schülerinnen. Manuskript III untersucht individuelle Unterschiede und zeigt, dass manche Schüler stärkere Schwankungen ihres fachspezifischen Selbstkonzepts erleben als andere. Selbstkonzeptinstabilität geht mit Prüfungsangst einher und ist ein Prädiktor für schlechtere Noten. Die vorliegende Dissertation konnte somit in einem intraindividuellen Ansatz zeigen, dass Lernsituation und individuelle Schülerressourcen zur Motivation in konkreten Lernumwelten beitragen. / This dissertation focuses on how student motivation emerges and changes in the day-to-day classroom context. Drawing on self-determination theory, it proposes that specific features of the classroom instruction—and of what teachers say and do—may either support or frustrate students’ need for autonomy. Autonomy-supportive instruction is hypothesized to enhance interest and competence perception in the classroom. At the same time, students’ classroom experience is affected by their individual resources such as interest, integrated values, or positive self-concepts. Given the dynamic nature of the classroom context, the overarching aim of this dissertation is to take a short-term, intraindividual approach to understand how both the learning situation and individual motivational resources shape students’ motivational experience. The dissertation comprises three manuscripts investigating student motivation in a pre–post design over a 1 year period, including a 3-week lesson-specific measurement phase in which students’ classroom experience were assessed daily. Drawing on interest theory, manuscript I shows that stable individual interest and perceived characteristics of classroom instruction make distinct contributions to students’ day-to-day interest experience. Similarly, manuscript II shows that both domain-specific self-concept and perceived characteristics of classroom instruction shape students’ felt competence in lessons. In particular, empirical support was found for the hypothesis that cognitive autonomy support has effects on student motivation over and above the effects of autonomy-supportive climate and controlling behaviors. From an individual differences perspective, manuscript III shows that some students experience higher day-to-day fluctuation in their domain-specific self-concepts than others. Self-concept instability was found to be associated with test anxiety and to predict lower school grades 1 year later. Taking a short-term intraindividual approach, this dissertation thus shows that both the learning situation and individual student resources contribute to motivation in context. An understanding of how motivation evolves over different contexts and time frames of instructional events, in everyday classroom life, and across the school career can usefully inform theories of motivation in context.

Background: The selection of a developmental time metric is useful in understanding causal processes that underlie cognitive change, and for the identification of potential moderators of cognitive decline. We examined various conceptualizations of developmental time (e.g., chronological age, measurement occasion, time-in-study, and time-to-attrition), and moderators of cognitive decline that are associated with CNS functioning (e.g., intraindividual variability and chronic health conditions). Methods: Participants were 304 community-dwelling Caucasian older adults (208 women and 96 men), aged 64 to 92 (M = 74.02, SD = 5.95) in a longitudinal study. HLM models were fit to examine patterns and moderators of cognitive change. Results: Time-to-attrition was associated with significant cognitive decline. Greater intraindividual variability, a behavioural indicator of CNS deficits, was associated with impaired performance on executive functioning and episodic memory measures. Conclusions: Our findings underscore the importance of selecting an appropriate time metric in order to address the possible causal mechanisms underlying the association between cognitive loss and selective attrition (i.e., CNS integrity).

Interessen werden meist aus einer Trait- oder State-Perspektive beforscht. Erst kürzlich wurden die beiden Perspektiven in einem theoretischen Modell integriert (Su et al., 2019), das postuliert, dass sich Interesse-Traits als intraindividuell variierende States manifestieren. Aufbauend auf dieses Modell untersucht die vorgelegte Dissertation Interessen anhand der wichtigsten Taxonomie für Interesse-Traits—Hollands (1997) Taxonomie beruflicher Interessen. Das Ziel dieser Dissertation ist zu untersuchen, ob und wie sich Berufsinteresse-Traits als States im Alltag manifestieren. Kernstück dieser Arbeit bilden zwei präregistrierte Experience Sampling Studien. Sie werden mit einem Literaturüberblick zu Interesse-Traits und -States eingeleitet sowie der Identifizierung von zwei Forschungszielen: Die Untersuchung (1) der Natur alltäglicher Manifestationen von Interesse-Traits und (2) der Korrelate von Interesse-States. Beide Studien verfolgten diese zwei Forschungsziele. Zentrale Ergebnisse waren, dass (1) Personen systematisch in ihren Interesse-States im Alltag variieren; (2) ein spezifisches Variabilitätsmuster in Interesse-States die Natur von Interesse-States von derjenigen von Persönlichkeit-States zu unterscheiden scheint; (3) Interesse-States systematisch mit spezifischen situations- und personenbezogenen Variablen assoziiert sind. Die Dissertation schließt mit einer Zusammenfassung, wie die beiden Studien zu den identifizierten Forschungszielen beitragen und einer Diskussion der allgemeinen Stärken, Limitationen und Anregungen für künftige Forschung. Theoretische Implikationen werden vorgestellt und in das integrative Modell (Su, et al., 2019) eingebettet. Insgesamt beleuchtet die vorgestellte Forschung die Natur und Korrelate momentaner Manifestationen von Berufsinteressen im täglichen Leben und kann künftige Forschung dazu anregen, stärker eine State-Perspektive auf Interessen zu berücksichtigen. / Research on interests is typically conducted with a trait or state perspective. Only recently, the two perspectives have been integrated within a theoretical model (Su et al., 2019), proposing that interest traits manifest as intraindividually varying states. Based on this model, this dissertation examines interests as conceptualized with the most prominent interest trait taxonomy—Holland’s (1997) taxonomy of vocational interests. With this dissertation, I sought to explore whether and how vocational interest traits manifest as states in daily life. Two preregistered experience sampling studies are this dissertation’s core. They are introduced with a literature overview on interest traits and states and an identification of two research goals: Exploring (1) the nature of interest trait manifestations in daily life and (2) correlates of interest states. While the first study provided first empirical answers on the nature and correlates of vocational interest states in daily life, the second study sought to refine these insights. The key findings of the two studies are that (1) persons systematically vary in their vocational interest states in daily life; (2) a distinctive pattern of interest state variability seems to set the nature of vocational interest states apart from the nature of Big Five personality states; (3) vocational interest states are systematically associated with specific situation- and person-related variables. The dissertation concludes with a summary of how the two studies contribute to the identified research goals and a discussion of the studies’ general strengths, limitations, and suggestions for further research. Theoretical implications are presented and associated with the integrative model of interests (Su, et al., 2019). Altogether, shedding light on the nature and correlates of vocational interest states in daily life, the presented research may encourage future work to consider a state perspective in research on vocational interests.