Maternal smoking during pregnancy has often been associated with numerous adverse outcomes for the offspring. However, its long-term effects are not well established. Given the high prevalence of maternal smoking during pregnancy, an understanding of these effects is essential. Therefore, the aim of the present dissertation was to shed light on the long-term neurophysiological effects of prenatal nicotine exposure on three different executive functioning processes by assessing participants in young adulthood, using functional magnetic resonance imaging (fMRI). Participants imaged were members of the Ottawa Prenatal Prospective Study, a longitudinal study that collected a unique body of information on participants from infancy to young adulthood, which allowed for the measurement of an unprecedented number of potentially confounding drug exposure variables. The dissertation consists of three separate original manuscripts. In manuscript 1, participants completed a response inhibition task, in manuscript 2 participants completed a verbal working memory task and in manuscript 3 participants completed a visuospatial working memory task. Taken together, results from all three manuscripts showed that prenatal nicotine exposure leads to altered neural functioning during executive functioning processing that continues into young adulthood. These significant results highlight the need for education about the repercussions of women smoking during pregnancy.

When examinees with the same ‘ability’ take a test, they should have an equal chance of responding correctly to an item irrespective of group membership. This logic in assessment is known as measurement invariance. The lack of invariance of the item-, bundle-, and test-difficulty across different subgroups indicates differential functioning (DF). The aim of this study is to advance our understanding of DF by detecting, predicting and explaining the sources of DF by gender in a mathematics test. The presence of DF means that the test scores of these examinees may fail to provide a valid measure of their performance. A framework for investigating DF was proposed, moving from the item-level to a more complex random-item level, which provides a theme of critiques of limitations in DF methods and explorations of some advances. A dataset of 11-year-olds of a high-stakes National mathematics examination from England was used in this study. The results are reported in three journal publication format papers. The first paper addressed the issue of understanding nonuniform differential item functioning (DIF) at the item- level. The nonuniform DIF is investigated because it is a possible threat when common DIF statistics sensitive to uniform DIF may indicate no significant DIF. This study differentiates two different types of nonuniform DIF, namely crossing and noncrossing DIF. Two commonly used DIF detection methods, namely the Logistic Regression (LR) procedure and the Rasch measurement model were used to identify crossing and noncrossing DIF. This paper concludes that items with nonuniform DIF do exist in empirical data; hence there is a need to include statistics sensitive to crossing DIF in item analysis. The second paper investigated the sources of DF via differential bundle functioning (DBF) because this way we may get a substantive explanations of DF - without which we do not know if DF is ‘valid’ or ‘biased’. Roussos and Stout’s (1996a) multidimensionality-based DIF paradigm was used with an extension of the LR procedure to detect DBF. Three qualitatively different content areas: test modality, curriculum domains and problem presentation were studied. This paper concludes that DBF in curriculum domains may elicit construct-relevant variance, and so may indicate 'real' differences, whereas problem presentation and test modality arguably includes construct-irrelevant variance and so may indicate gender bias. Finally, the third paper considered item-person responses as hierarchically nested within items. Hence a two-level logistic model was used to model the random item effects, because otherwise it is argued that DF might be over-exaggerated and may lead to invalid inferences. This paper aimed to explain DF via DBF comparing single-level and two-level models. The DIF effects of the single-level model were found to be attenuated in the two-level model. A discussion of why the two different models produced different results was presented. Taken together, this thesis shows how validity arguments regarding bias should not be reduced to DF at item-level but can be analysed on three different levels.

Magister Artium (Social Work) - MA(SW) / Adolescence has been regarded as a particularly important stage for the continued development of young adults as they start to make their own life’s decisions and engage in a variety of activities that will influence the rest of their lives. One of the important goals of adolescence is the development of decision-making skills as independence increases, requiring more independent decisions. When an adolescent makes decisions, it is important that s/he has the skills to make confident ones. Various studies identify factors that could affect adolescent decision-making, such as the family environment and family-member relationships, but information pertaining to this subject is still relatively limited. This study examines the role of family functioning in the decision-making styles of adolescents. The theoretical framework used for this study is based on the Family Systems Theory, of which the McMaster Model of Family Functioning (MMFF) is a component. The MMFF is one variation that underlies the family system model, be it nuclear or extended families discussed within chapter 2. A quantitative methodological approach was employed in this study with a cross-sectional correlational research design. The sample consisted of 457 Grade 9 learners from schools in the Overberg area. The data was collected using a self-reported questionnaire that included the Demographic Information, the Family Assessment Device and the Melbourne Decision Making Questionnaire, as part of the quantitative methodology. The data was then analysed using the Statistical Package for Social Sciences V22 (SPSS). The results were provided using descriptive and inferential statistics. Participation in this study was voluntary after being well informed, while confidentiality and anonymity was maintained throughout the study. The main results for family functioning indicated the assumption that the participants might have ineffective functioning on all the family functioning variables. The main results for decision-making styles showed an assumption that the vigilant decision-making style was the highest and the Buck-passing decision-making style, the lowest.

This study examined peer relationships and psychosocial functioning as a function of maternal and paternal involvement and nurturance along with the moderating effects of gender, family form, and ethnicity. Prior research has shown the influence of mother’s involvement on peer relationship quality but not of fathers. Further, previous studies did not examine moderation by family form, gender, or ethnicity. The sample consisted of 1359 students who identified their biological mother and father as the most influential parental figures in their lives. Their ages ranged from 18 to 26; Sixty–one percent of the sample was Hispanic, 13% non-Hispanic Black, 25% non-Hispanic White; 76% female and 70% from intact families. The analytical strategy included using bivariate correlations and structural equation modeling to examine these relationships. All dimensions of maternal and paternal nurturing and involvement were positively related to positive characteristics of peer relationships, self-esteem and life satisfaction consistent with the multicultural findings of PARTheory (Rohner, Khalique, & Cournoyer, 2005). A structural model was developed that was able to adequately account for the relationship between parental influence, peer relationships, and psychosocial functioning. These effects of both maternal and paternal influence were strongly moderated by culture, family form, and gender. Finally, a differential effect was found among parental influence with fathers having a greater influence on friendship quality and importance than mothers, despite greater maternal involvement. These findings have theoretical, clinical, and social implications as they call for a socially based theoretical perspective within which to study these relationships. Such a perspective would better inform clinicians when using impaired social functioning as indicative of axial diagnosis, and for the implementation of social policy to encourage paternal involvement.

No description available.

The restoration of degraded tallgrass prairies can mitigate climate change due to the carbon accrued during the development of grasslands. The focal species, dominant grass Andropogon gerardii, can assist the recovery of grassland ecosystem functioning. Climate, local adaptation, and biodiversity have been found to impact the accrual of carbon in grasslands. This study examined the difference in ecosystem functioning between ecotypes along a dry to mesic precipitation scale. The study site for this project was at the Southern Illinois University Agriculture Research Center in Carbondale, Illinois. The field site was planted with seeds originating from dry to mesic ecotypes, and the resulting ecosystem functioning was analyzed. It was found that the Kansas non-local ecotypes had significantly higher biodiversity, while the local Illinois sites demonstrated local adaptation with A. gerardii. Aboveground plant biomass was higher in the local sites, but there was no difference in carbon accrual between any of the ecotypes. While ecotypic variation in a dominant species will usually differentially influence ecosystem functioning, in this case, high biodiversity and local adaptation result in similar carbon inputs in grassland soil. It is necessary to analyze the carbon content of the soil in the drier field sites in order to determine if major differences in rainfall leads to differences in carbon accrual. If the goal of restoring a tallgrass prairie in southern Illinois is to assist with climate change mitigation, then it does not make a significant difference if the dominant species is sourced locally or non-locally.

Research has investigated testosterone and its role in biological and psychological functioning. Testosterone levels decrease as men age, and aging has been associated with declines in muscle mass and strength. Decreased functional mobility can impact quality of life. Aging has also been associated with increased vulnerability to depressive symptomatology. The purpose of this study was to investigate interrelationships among testosterone, physical functioning, quality of life, and depression in the Vietnam Era Twin Study of Aging (VETSA). The mean age of the 1,237 men in VETSA was 55.4 (+2.5). Testosterone data collection began in the third year of VETSA, yielding an available sample of 778. It was hypothesized that there would be significant associations between testosterone and physical functioning, depression, and quality of life as well as between physical functioning and depression and quality of life. Contrary to expectations, when mixed models for linear regression were used, testosterone was shown to be related only to physical functioning. As predicted, however, physical functioning was significantly related to depression and quality of life. Cholesky decompositions were conducted to address the hypothesis that there were shared genetic determinants of each phenotype. Best fitting bivariate models included additive genetic and unique environmental but not common environmental influences. Significant genetic correlations were found between physical functioning and depression, and physical functioning and the mental health component score of the Short Form Health Survey (SF-36). Contrary to expectations, while testosterone and physical functioning were significantly correlated with each other phenotypically, there was no genetic correlation between the two. Trivariate models revealed genetic influences specific to depression as well as genetic influences shared with quality of life and depression. Finally, path analysis demonstrated that testosterone had a direct impact on physical functioning. Physical functioning, but not testosterone, directly impacted depression and quality of life. As there was no genetic correlation between testosterone and physical functioning, but there was a phenotypic correlation, it may be that other factors, such as cortisol, influenced the association. In sum, in this sample, physical functioning seemed to be more important than testosterone to both depressive symptomatology and quality of life.

The current study examined 236 undergraduate students in a week long twice-per-day ecological momentary assessment exploring the influence of baseline reward sensitivity and interactions between circadian variables (i.e., total sleep time, sleep quality) and daily measures of reward. Though primary study findings did not support reward sensitivity related moderation of sleep-reward pathways, a number of notable findings emerged. We found evidence of specific domains of reward sensitivity (anticipatory reward and reward responsiveness) which are uniquely related to daily experiences of reward. In addition, bidirectional circadian-reward pathways were found between sleep quality and daily rewards which suggests pathways towards reward-related engagement. Evidence also supported interactions between sleep quality and total sleep time on experience of daily reward, further highlighting the complexity of sleep-reward pathways and their relevance to mood symptoms.

This prospective longitudinal study evaluated the effect of prenatal cocaine exposure (PCE) on executive functioning in 5- and 7-year-old children. In total, 154 pregnant cocaine users, identified by urine toxicology and structured interviews, were matched to 154 nonusers. Children were assessed by certified masked evaluators, and caregivers were interviewed by experienced staff during home visits. In approximately 90% of the surviving sample tested at ages 5 and 7 years, structural equation modeling demonstrated that an increased head circumference at birth (adjusted for gestation) significantly predicted better performance on executive functioning, and that PCE was indirectly related to executive functioning through its significant negative effect on head circumference at birth. At age 5 years, quality of environment also predicted executive functioning, and the R2 for the total model was 0.24. At 7 years, caregiver functioning predicted quality of environment, which in turn was positively related to executive functioning, and girls had better executive functioning. The total model at age 7 years accounted for 30% of the variance in executive functioning.

Introduction: Defensive functioning may play an important role in the development and treatment of binge-eating disorder (BED). The Defense Mechanism Rating Scale (DMRS) is a widely used observer rating measure of defensive functioning. However, there is little research on defensive functioning and the DMRS in BED. This dissertation includes three studies on defensive functioning in individuals with BED. Study one assessed the validity and reliability of the DMRS when used to rate Adult Attachment Interview (AAI) transcripts, and compared defensive functioning between women with and without BED. Study two compared change in defensive functioning in women with BED who received Group Psychodynamic-Interpersonal Psychotherapy (GPIP) versus those in a waitlist no treatment control condition. Study three assessed the impact of other group therapy members’ defensive functioning on an individual group member’s treatment outcomes (i.e., binge-eating frequency and interpersonal functioning). Thus, the overall goals of this dissertation were to better understand the role of defensive functioning in BED, the degree to which defensive functioning changes due to group therapy, and the impact in the context of the therapy group’s defensive functioning on individual outcomes. Method: Participants with for this study were recruited from three previous investigations. Two clinical trials of group psychotherapy provided data of individuals with BED: (1) a randomized trial (N = 85) in which participants were assigned to GPIP (n = 35) or a waitlist control (n = 50), and (2) an uncontrolled study in which all participants with BED (N = 101) received GPIP. A total of 17 therapy groups were formed across both studies, with each group consisting of five to 11 members. In addition, a third study provided data from two comparison groups without BED: women who were overweight/obese (body mass index [BMI] > 27 kg/m2; n = 47) and women who were normal weight (BMI = 20 to 25 kg/m2; n = 49). Participants with BED completed a battery of questionnaires and the AAI at two time-points (i.e., pre-treatment/pre-waitlist and six months post-treatment/post-waitlist). Participants without BED completed the same battery of questionnaires and the AAI at one time-point and did not receive treatment. All AAI audio recordings were transcribed and used to code defensive functioning. Results: In study one, the DMRS coded from AAI transcripts demonstrated acceptable inter-rater reliability; good convergent validity, as it was significantly correlated with other related constructs (i.e., interpersonal functioning, reflective functioning, and attachment insecurity); and acceptable predictive validity, as women with BED had significantly lower defensive functioning than normal weight women without BED. In study two, those who received GPIP had significantly greater improvements in defensive functioning from pre-treatment to six months post-treatment compared to the waitlist control group. Follow-up analyses revealed that the average number of High Adaptive defenses significantly increased from pre-treatment to six months post-treatment in the GPIP condition, but not in the waitlist control condition; and significantly more participants assigned to the waitlist control condition deteriorated in their defensive functioning from pre-waitlist to six months post-waitlist than those assigned to GPIP. In study three, individual defensive functioning scores at pre-treatment were not significantly associated with either treatment outcome (i.e., binge-eating frequency or interpersonal distress) at six months post-treatment. However, other group members’ mean defensive functioning scores at pre-treatment were significantly associated with individual interpersonal distress, but not binge-eating frequency, at six months post-treatment. Discussion: Overall, this dissertation lends further support to the role of defensive functioning in the maintenance and treatment of BED. Individuals with BED tend to use less adaptive defensive functioning, but this can be improved through GPIP. Further, context of the therapy group in terms of defensive functioning is particularly important for improving treatment outcomes in individuals with BED. These findings should be replicated across more diverse samples and other types of group psychotherapy. Group therapists can help their patients with BED confront their maladaptive defense mechanisms and binge-eating by tackling their interpersonal distress, and placing sufficient emphasis on the group’s composition in terms of defensive functioning.