Psychology Theses and Dissertations

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https://hdl.handle.net/1794/995

This collection contains some of the theses and dissertations produced by students in the University of Oregon Psychology Graduate Program. Paper copies of these and other dissertations and theses are available through the UO Libraries.

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Browsing Psychology Theses and Dissertations by Subject "adolescence"

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    Sensitive Periods for Social Development in Adolescence: Exploring Mechanisms Relating Experience and Timing to Neural Change
    (University of Oregon, 2021-11-23) Cheng, Theresa; Pfeifer, Jennifer
    Social relationships during adolescence have outsized effects on long-term physical and mental health. The theory that adolescence is a sensitive period suggests that adolescent experiences might profoundly shape development. Part of this dissertation reviewed empirical evidence in consideration of the theory that adolescence is a sensitive period for sociocultural development. Despite clearer knowledge about neurodevelopmental and social changes occurring during adolescence, we identified major remaining gaps in our understanding of how adolescent experiences may become neurally embedded in the long-term.The current investigation used pediatric neuroimaging to evaluate evidence for such neural embedding within a frontostriatal circuit thought to undergo protracted development in adolescence (specifically, nucleus accumbens and ventromedial prefrontal cortex). We tested a long-term phasic modeling hypothesis that phasic, task-evoked brain connectivity sculpts or influences more “intrinsic” or baseline measures of connectivity over long developmental times-scales. Adolescent self-disclosure was examined as a candidate process for long-term phasic modeling due to its ubiquity, frequency, and significance in deepening peer relationships, as well as its ability to elicit neural signal within the target circuit. Analyses of data from a longitudinal community sample that recruited adolescent girls (initial N=174; initial ages 10.0-13.0 years, 18 mos. between waves) examined (1) developmental trajectories, (2) developmental mechanisms, and (3) behavioral outcomes associated with frontostriatal connectivity across states of task and rest. Results identified nonlinear puberty-related changes to functional connectivity during self-disclosure and found that this connectivity may be related to friendship quality. However, results did not identify developmental patterns consistent with long-term phasic modeling hypothesis, an alternative (reverse) hypothesis, or with sensitive periods in frontostriatal connectivity. Instead, a developmental pattern consistent with the long-term phasic modeling hypothesis described connectivity between one of the nodes (the nucleus accumbens) and a control region within the primary visual cortex and further suggested that connectivity between these regions may be related to real world friendship behaviors. More work is needed to understand the robustness, specificity, and translational relevance of this effect. This research highlights a viable analysis strategy for examining developmental and sensitive period mechanisms with multiple waves of longitudinal data.
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    The Freshman Project: Adolescent Well-Being During the Transition to College
    (University of Oregon, 2020-12-08) Mobasser, Arian; Pfeifer, Jennifer
    Adolescence is a critical period of development during which myriad biological and ecological changes converge with youths’ burgeoning sense of self-awareness. Despite enduring views of this convergence as one of only stress and strife, scientists increasingly consider the degree to which it also presents opportunities for positive growth. One such opportunity is rooted in adolescents’ own evaluations of their positive feelings and functioning, commonly referred to in the scientific literature as well-being. While research points toward the importance of well-being for positive development, there is much yet unknown about its precise form and function, especially during later stages of adolescence. Advancing this science may enable us to better understand and support positive developmental trajectories into adulthood. The current dissertation is organized into two main sections. In the first section (Chapter I), recent research on the effects of digital technology provides the basis upon which to highlight common methodological and theoretical limitations in the existing science of adolescent well-being. Situated within a broader review, I discuss ways in which improved conceptual precision and stronger theory can help to propel the field forward. The second section (Chapters II-V) presents an empirical study of a relatively understudied area: well-being during the transition to college. Previous research has explored the effects of college on well-being; however, studies have generally ignored the ways in which the unique developmental tasks of this period may correspond to a set of criteria for being well that differs from that of younger adolescents and older adults. To help address this gap, the structure of well-being in college-aged adolescents (N = 573) was investigated using exploratory factor analyses and then confirmed in a sample of incoming college students (N = 274) within a structural equation modeling framework. The best-fitting model consisted of eight facets nested within two superordinate factors which correspond, respectively, to hedonic and eudaimonic dimensions of well-being. Developmental trajectories of well-being were then examined longitudinally. Second-order latent growth curve models showed significant decreases in well-being during the first year of college. Together, this dissertation contributes to the scientific understanding of the structure and development of well-being during adolescence.