Theses and Dissertations from UMD
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Item Individual and Interactive effects of child and parent anxiety on behaviorally inhibited youth's RSA across social stressor tasks(2023) Bui, Hong Nhu Thi; Chronis-Tuscano, Andrea; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Children with elevated behavioral inhibition (BI) show context-inappropriate fear and dysregulated RSA across stressor tasks. However, few studies have examined dynamic RSA within tasks and relations to parent and child anxiety. Using piecewise growth modeling and multi-method baseline data from an intervention study of 151 3.5-5 year old children and their parents, the individual and interactive influences of child social anxiety (SA) and parent anxiety (via diagnostic interviews) in predicting children’s RSA across social stressor tasks (e.g.,learning about unfamiliar peers, Trier Social Stress) were tested. Children high in SA showed RSA responses indicative of avoidant coping, whereas those low in SA showed responses suggesting attention in anticipation of meeting unfamiliar peers. The relation between child SA and RSA across tasks was moderated by parent anxiety, specifically for dyads matched in anxiety. Findings provide support for the influence of both child and parent anxiety on children’s RSA response across specific stressor and non-stressor tasks.Item Neuroendocrine mechanisms underlying paternal experience-induced plasticity of the hippocampus(2016) Hyer, Molly Melissa; Glasper, Erica R; Neuroscience and Cognitive Science; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Evidence suggests that males, like females, undergo altered structure and function of the hippocampus postpartum, a brain region that regulates certain aspects of emotion, learning, and memory. These behaviors are beneficial for successful parenting. In maternal rodents, offspring contact contributes to postpartum hippocampal plasticity in both mothers and offspring. Fathers do not undergo pregnancy, parturition, or lactation, therefore, the impact of offspring on hippocampal plasticity is less clear. California mouse (Peromyscus californicus) fathers are highly paternal, making this monogamous species a good model of paternal care. In this species, between postnatal days 15 and 21 paternal behavior becomes more active (i.e. increased pup retrievals) to care for pups that are beginning to explore outside of the nest. I observed reduced anxiety-like behavior in fathers specifically within this temporal window. Concomitant with attenuated anxiety-like behavior, I found that fathers maintain survival of adult born neurons in the dentate gyrus of the hippocampus. Enhanced hippocampal plasticity is not restricted to adult neurogenesis, as dendritic spine density in the dentate gyrus is increased in fathers at this same time – an effect that lasts until weaning. When permanently separated from their offspring, fathers show increased passive stress coping and reduced spine density in the DG. Taken together, these data suggest that the degree of active father-offspring interaction significantly alters hippocampal plasticity in the father. Estradiol and its receptors have been implicated in alterations to anxiety and adult neurogenesis in both males and females. I observed that estrogen receptor β (Erβ) mRNA expression was elevated in whole hippocampal homogenates at PND 16 in fathers. Similarly, circulating estradiol was elevated at both PND 2 and PND 16. After inhibition of Erβ with the drug tamoxifen, the number of surviving adult born neurons was suppressed in fathers alone. Taken together, these data suggest that in fathers, hippocampal plasticity occurs concomitantly with active father-offspring contact and that this plasticity, at least structural, is driven by activation of Erβ. Understanding paternal experience-induced plasticity and the mechanisms that drive it, may help to prevent deficits in paternal behavior that can disrupt offspring development and contribute to emotional dysregulation in fathers.Item THE INFLUENCE OF CONSCIOUS CONTROL OF MOVEMENT ON BRAIN PROCESSES AND THE QUALITY OF COGNITIVE-MOTOR PERFORMANCE(2015) Lo, Li-Chuan; Hatfield, Bradley D.; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)The impact of mental stress on fine motor performance is typically maladaptive. The current research was conducted to investigate the manner by which state anxiety affects performance using a cognitive neuroscience perspective. The basic proposition tested, derived from the Reinvestment Theory and the Psychomotor Efficiency Hypothesis, is that stress introduces neuromotor noise to motor planning processes that translate as excess recruitment of motor units and degrade performance. Electroencephalography (EEG) was employed in Study 1 to assess regional cortical activation and cortico-cortical communication between non-motor associative and motor planning regions during the preparatory period of a dart-throwing task. The task was performed during stress (i.e., social evaluation, monetary incentives, and threat of electrical shock) and a relatively relaxed control condition through a within-subjects design. Regional activation was estimated from bilateral EEG recordings in the frontal, central, temporal, parietal, and occipital regions via spectral analysis to assess low-alpha and high-alpha band power to determine generalized arousal and task-relevant attentional focus, respectively. Cortico-cortical communication was estimated between all bilateral regions and the frontal motor planning area with particular emphasis on the left temporal (T3) to midline frontal (Fz) coherence. Elevated state anxiety was induced and associated with heightened T3-Fz EEG connectivity and synchrony of high-alpha band in the right occipital region. Based on these findings, Study 2 was conducted to determine the psychological processes accounting for the observed elevation in T3-Fz EEG coherence and the quality of muscle action during the throwing task. Specifically, participants employed an internal and an external attentional focus to perform the throwing task while their EEG and electromyography (EMG) were monitored. The use of internal focus, which is consistent with explicit monitoring of movement mechanics, was predicted to result in elevated T3-Fz EEG connectivity. This prediction was supported and, furthermore, the magnitude of connectivity was positively associated with motor unit activity assessed via EMG of four major muscle groups (i.e., flexor carpi ulnaris, extensor carpi radialis, biceps brachii, and triceps brachii). The evidence provided supports the theoretical notion that explicit monitoring promotes inefficient muscle activity, which mediates to impact performance negatively.Item A Longitudinal Examination of the Relationship between Childhood Emotional Abuse and Anxiety among Youth: Distress Tolerance as a Mediating and Moderating Factor(2014) Banducci, Anne Nicole; Lejuez, Carl; MacPherson, Laura; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Background: Anxiety is the most common psychological problem experienced by youth. A number of factors are associated with the emergence of anxiety, including individual and environmental factors. Two such factors include childhood emotional abuse (CEA) and low distress tolerance (DT). The current study aimed to understand how more severe CEA and lower DT impacted anxiety symptoms among community youth. Specifically, we examined low DT both as a moderator and mediator in the relationship between CEA and anxiety. Methods: Participants were two cohorts of community youth. Cohort 1 included 244 youth (54% male, 50% White, 35% Black, 3% Hispanic, 11% mixed/other) with a mean baseline age of 12.01 years (SD = 0.82) assessed annually over five years. Cohort 2 included 109 youth (60% male, 11% White, 79% Black, 10% mixed/other) with a mean baseline age of 10.87 years (SD = 1.28) assessed annually over three years. Measures included the Revised Child Anxiety and Depression Scale, Childhood Trauma Questionnaire, and Behavioral Indicator of Resiliency to Distress. Results: In cohort 1, more severe CEA was associated with higher anxiety at baseline and with sharper decreases in anxiety over time. Lower DT was associated with higher anxiety at baseline, but did not predict changes in anxiety over time. Distress tolerance significantly moderated the relationship between CEA and anxiety, such that youth with both low DT and more severe CEA had the highest anxiety across all five assessments. Results using data from cohort 2 were not significant. Conclusions: These findings suggest lower DT amplifies the relationship between CEA and anxiety, such that youth with lower DT, who have been abused, are less likely to experience normalization in anxiety symptoms over time compared to youth with higher DT. These findings are in line with diathesis-stress models common to developmental psychopathology.Item The effect of mental stress on brain dynamics and performance related to attention control during a vigilance task: An electroencephalographic investigation(2013) Russell, Bartlett Anne Healy; Hatfield, Bradley D; Neuroscience and Cognitive Science; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Anxiety can increase distractibility and undermine the quality of psychomotor performance. Models of attention processing postulate that anxiety consumes limited executive resources necessary for maintaining goal-oriented, "top-down" attention control and suppressing stimulus-driven "bottom-up" distraction. Attention Control Theory (ACT) predicts that anxiety adversely affects the efficiency, and particularly inhibitory components of executive, frontally mediated top-down attention control. We used two approaches for examining this model. First, though attention affects synchrony among neural structures, information regarding how human oscillatory patterns (measured with electroencephalography, EEG) change as state anxiety increases is limited. Second, while anxiety affects the balance between top-down and bottom-up mechanisms, to our knowledge no one has yet measured anxiety's effect on attention using a neural measure of top-down control in conjunction with more traditional bottom-up measures of attention capture (e.g., the P3 event related potential, or ERP). Purpose: Study 1 examines the oscillatory patterns (spectral dynamics) of the cortex in order to investigate whether frontal regions exhibit patterns of reduced efficiency and altered networking with posterior regions during threat of shock. In order to assess the relationship between top-down and bottom-up attention dynamics, Study 2 uses the same threat protocol to measure attention-directed top-down modulation of sensory signaling (steady-state visual evoked potential, or ssVEP modulation) and of bottom-up attention capture by discrete targets and distractors (Event Related Potentials, ERPs). Results: The spectral analyses in Study 1 suggest decreased processing efficiency and decreased frontal networking (coherence) with more posterior regions as anxiety increased. Reduced coherence, however, could indicate either increased or decreased top-down focus; Study 2 provides more insight. Neural responses to task-relevant targets (ERPs) diminished as threat increased, while responses to task-irrelevant distractors remained unchanged. Contrary to what ACT would predict, we observed an increase in attention modulation of an ssVEP frequency associated with amplifying the task-relevant signal and no change in an ssVEP associated with inhibiting task-irrelevant stimuli. These findings suggest top-down attention control increased under threat, but was not enough to prevent degraded processing of task-relevant targets coincident with reduced efficiency on task performance. Implications and suggestions for refining ACT are discussed.Item Developmental Alterations in Inhibitory Neurotransmission in the Fragile X Syndrome Mouse Basolateral Amygdala(2012) Kratovac, Sebila; Corbin, Joshua G; Biology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Fragile X Syndrome, caused by Fmr1 gene inactivation, is characterized by symptoms including enhanced fear, hyperactivity, social anxiety, and autism, pointing to synaptic and neural circuit defects in the amygdala. Previous studies in Fmr1 knockout (KO) mice have demonstrated alterations in GABAA receptor (GABAAR) function in the basolateral amygdala during early postnatal development. In this study, we sought to determine whether these early defects in GABAAR function are accompanied by changes in protein expression of GABAAR alpha 1, 2, and 3 subunits, the pre-synaptic GABA-synthesizing proteins GAD65 and 67 (GAD65/67), and the post-synaptic GABAAR-clustering protein gephyrin. We found that the developmental trajectory of protein expression is altered in knockout mice for all tested proteins except GABAAR alpha 3 and GAD 65/67. Our results suggest that alterations in the timing of inhibitory synapse protein expression in early postnatal development could contribute to observed inhibitory neurotransmission deficits in the KO mouse basolateral amygdala.Item PERSONAL RELATIONSHIP COMMITMENT, POSITIVE AND ANXIOUS EMOTIONAL AROUSAL, AND COMMUNICATION IN CLINIC COUPLES(2009) Mena, Leidy Magdalena; Esptein, Norman B.; Family Studies; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)This study examined relationships among partners' relationship commitment, positive and anxious forms of emotional arousal prior to engaging in a discussion of a conflictual relationship issue, and subsequent communication behavior, in a sample of clinical couples who had experienced psychologically and mild to moderate physically abusive interactions. A secondary analysis was conducted with data from 68 couples who had sought therapy for relationship problems. Results indicated that men and women with higher commitment experienced less anxious arousal and more positive emotional arousal prior to engaging in problem-solving. Greater commitment in men was associated with more constructive communication behaviors, and women with higher levels of anxiety engaged in more negative communication. Men's positive emotional arousal was associated with more positive communication behavior and less negative communication behavior. Men's positive emotional arousal mediated between commitment and constructive communication behaviors; however, anxious emotional arousal did not. Implications for couple therapy are discussed.Item Gender Differences In Parenting, Adolescent Functioning, and The Relation Between Parenting and Adolescent Functioning In Urban Mainland Chinese Families(2008-04-28) Quach, Andrew; Epstein, Norman; Family Studies; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)ABSTRACT Adolescents living in Mainland China generally experience high levels of demands from their parents to perform well in school, and this may negatively impact Chinese adolescents' psychological functioning (Siu & Watkins, 1997). Secondary data from 997 urban Mainland Chinese high school students from four Beijing schools were used to examine relations of parental warmth and parental control with adolescent academic achievement, depression, and anxiety. The present study also examined whether adolescent functioning and associations between parental behaviors and adolescent functioning differed by gender of the parent and child. Independent t-tests, correlations, and multiple regression analyses found no significant gender differences in adolescent academic achievement, depression, and anxiety. Overall, father's and mother's warmth were positively associated with academic achievement and negatively associated with depression and anxiety, whereas parental control was negatively associated with academic achievement and positively associated with depression and anxiety. Paternal and maternal warmth moderated the association between paternal and maternal control and boys' and girls' depression and anxiety. There were minimal gender differences in the associations between parental behaviors and adolescent functioning. Only maternal and paternal pressure had a stronger association with boys' depression than with girls' depression. Results suggest the importance of using warmth in the parent-child dyad, especially regarding academic expectations for boys, and not basing behaviors on preconceived notions of gender roles.Item The best friendships of young adolescents: The role of internalizing symptoms, characteristics of friends, friendship quality, and observed disclosure(2008-01-15) Buskirk-Cohen, Allison Anne; Rubin, Kenneth H; Human Development; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)The best friendships of emotionally distressed and typical young adolescents were investigated. A group of 5th and 6th grade young adolescents completed ratings on friendship quality and participated in videotaped friendship tasks. Emotional distress was identified using a T score cut-point of 60 on the Internalizing symptoms subscale of the Child Behavior Checklist (CBCL). There were 131 friendship dyads available for analyses. Of these, 48 were considered distressed dyads (24 female dyads; 24 male dyads) and 83 were considered typical dyads (47 female dyads; 36 male dyads). Results demonstrated similarity of internalizing symptoms between best friends of typical adolescents, but not distressed adolescents. Analyses on friendship quality ratings emphasized the importance of perspective. Distressed targets rated their friendships lower on validation/caring, help/guidance and total positive friendship quality than did typical targets. However, friends of distressed adolescents did not rate their friendships differently than friends of typical adolescents. Congruent with past research, females tended to rate their friendships higher on intimate disclosure than did males. No developmental differences emerged in analyses of friendship quality. Regarding observed disclosure, only half of the dyads engaged in spontaneous disclosure talk. The majority of disclosures involved negative speech about the self or dyad. Females tended to devote more time to disclosure talk and respond to disclosure in more positive ways than males. Fifth-graders tended to devote more time to disclosure talk, initiate more disclosures and respond in more negative ways than 6th graders. Differences between distressed and typical dyads did not emerge in analyses of observed disclosure. Finally, relations between reported friendship quality and observed disclosure were explored. Overall, a lack of relation among variables suggests that the ways in which adolescents think about friendship quality are not related to visible interactions that took place in the laboratory.Item Social Phobia and Occupational Functioning(2005-07-26) Yeganeh, Robin; Beidel, Deborah C; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)ABSTRACT Title of dissertation: SOCIAL PHOBIA AND OCCUPATIONAL FUNCTIONING Robin Yeganeh, Doctor of Philosophy, 2005 Dissertation directed by: Professor Deborah C. Beidel Department of Psychology Although there is substantial research on the psychopathology and social functioning of socially anxious adults, there has been little effort to study how this disorder impacts occupational functioning. The few studies that exist to date indicate that adults with social phobia have impaired occupational functioning due to their social fears. For example, 92.3% of one socially phobic sample reported some type of occupational impairment (Turner et al., 1986) and in another study, social fear affected attainment of employment and acceptance of job offers or job promotions (Stein et al., 2000). Objective: This study was designed to further elucidate the type of occupational impairment found among those with social phobia by conducting a comparison to a non-anxious control group. Method: Study participants were those who meet DSM-IV diagnostic criteria for a primary diagnosis of Social Phobia and work at least 20 hours a week. Semi-structured interviews were used to diagnose psychiatric disorders. In addition, self report measures and a daily work diary will be used to examine anxiety, satisfaction with work, and work behaviors. Results: Socially phobic patients were significantly less likely to initiate conversations and engage in interactions with coworkers. Likewise, they reported higher levels of anxiety than non-anxious controls during interactions. Their anxiety prevented their ability to communicate with coworkers, despite a desire to do so. They also report greater hardship in relationships at work in comparison to normal controls. Conclusions: Additional studies on the relationship between anxiety and work functioning are needed. Treatments developed to increase work functioning are warranted. The findings of this study have implications for organizational interventions aimed at increasing quality of work life and work related social functioning for employees with social anxiety.