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Studies have indicated that separate use of the technique of priming and recasting can increase the use of complex syntax by children with and without specific language impairment (SLI). The current study was devised to examine whether children with SLI differ from children who are typically developing (TD) in the use of relative clauses in response to an intervention composed of a combination of priming and recasting. Twenty-six children (13 with SLI and 13 TD) ranging in age from 6 years, 10 months to 10 years, 11 months participated in the study. Forty pairs of stimulus pictures and sentences for each relative clause type (SR and OR) were created. The examiner presented the picture and read a sentence to the participant. Next, a new picture was shown and the participant created a sentence. The examiner then recasted the participants’ responses into the desired syntactic form. A preliminary ANOVA for the trials to criteria (3 out of 4 consecutive correct responses) for the subject relative and object relative clauses revealed nonsignificant main effects for Order and Group by Order interactions. A two-way mixed ANOVA was conducted to assess differences between the two groups and the two sentence types when compared with the trials to criteria scores. There was a significant effect for group where the SLI group required more trials to reach the criteria for both sentence types than the TD group. Additionally, the subject relative sentences were easier for the participants in both groups (TD and SLI) than the object relative sentences. A regression analysis conducted to predict the trials to criteria scores for both sentence types using the participants’ age, CELF raw score, and UNIT raw score revealed that the CELF raw score was significantly related to the trails to criteria score for the two sentence types. When additional analysis of the group and sentence type interaction was completed with the CELF raw score as a covariate, the group main effect was no longer significant. Analyses of the error patterns observed in the sentences produced by the participants as well as implications of the results are discussed.

The prevalence of drugged driving has increased in the United States, and some prescription medications (e.g., zolpidem) cause impairment after the predicted duration of therapeutic action has elapsed. The aim of this study is to determine if bedtime administration of alprazolam similarly impacts driving performance the following day. Volunteers were 14 healthy adults (6 males) who completed a double-blind, double-dummy within-subjects design study examining the effects of alprazolam (0.5, 1, & 2mg), zolpidem (10mg), and placebo administered at bedtime on driving performance the following day. The positive control condition was alprazolam (1mg) administered on the test morning. Driving simulator measures, cognitive and psychomotor tasks, and questionnaires querying drug effects were collected the afternoon before drug administration and for 5.5 hours the next day and analyzed using symmetry and mixed-model approaches. The positive control was robustly impairing. Driving impairment equivalent to that seen with alcohol at the legal limit was observed up to 12.5hr after bedtime alprazolam 2mg and for 8.5hr after bedtime zolpidem 10mg. Volunteers were not fully aware of their own level of impairment. These results suggest that alprazolam used before bed may pose an as yet unrecognized public safety risk in the form of next-day drugged-driving.

The aging population in the United States will increase drastically in the next decades. Consequently, the field of aging will need more social workers. Beyond the usual cognitive decline of this stage in life, older adults may face conditions that include cognitive impairment, such as Alzheimer’s disease and Parkinson’s disease. This research studied the extent to which personal experience and previous work exposure influences social work students’ interest in working with the elderly with cognitive impairment. This study used a cross-sectional survey design and collected the participants’ answers using a survey which was sent out through classroom visits and online via email; participants’ answers (n=133) were analyzed using a quantitative method. Results suggested that previous work exposure to an elderly with cognitive impairment has influence on the students’ current interest, while previous experience through interaction with family and friends was not an influence. Findings from this study may help promote the creation of internships or other ways of supporting social work students interested in developing a career in aging, as an increase in the number of future social workers in this field will help fulfill the needs of older adults.

Healthcare professionals who practice while impaired by alcohol or drugs endanger the well-being of patients. In the workplace, the substance-impaired healthcare professional poses challenges for healthcare leaders who are responsible for the provision of safe patient care and safe work environments. The purpose of this multiple case study was to explore management strategies used by some healthcare organizational leaders to address the substance-impaired healthcare professional in the workplace. The conceptual framework for this study drew upon the legal and ethical concepts of due diligence. Data collection consisted of surveys of 40 managers and supervisors, and 3 senior leaders, semi structured interviews of executive leaders from one large hospital, and a review of company documents. A software program was used to organize the data for analysis. Five themes emerged that yielded 6 possible strategies that leaders could use to address the substance-impaired healthcare professional in the workplace: an affective healthcare business model, healthcare leader training, monitoring and surveillance systems, synergistic integration of work and life balance, and legal and ethical incident reporting. These research findings may contribute to positive organizational and social change by reducing the risk patients have from substance-impaired healthcare professionals.

Language impairment (LI) and ADHD are two relatively common developmental disorders that frequently co-occur and have thus been said to be comorbid. The overall aim of this research is to investigate the nature of comorbidity between LI and ADHD in a large population-based sample. The project comprises two parts. The first study aims to quantify the extent of comorbidity between LI and ADHD, and asks whether there is any evidence for a shared liability between the two disorders on the basis of family history data. The second study hypothesizes that comorbidity between LI and ADHD arises because the two disorders share a common genetic etiology. Genetic variants previously associated with ADHD are tested for association to LI. Association is found with the dopamine receptor D4 (DRD4) and the serotonin transporter gene (SLC6A4). Implications for this in relation to language are discussed with respect to reinforcement and associative learning.

Although there are ample studies confirming that memory self-efficacy (MSE) declines with age, less is known about what factors account for the variation in MSE among older adults. The purpose of this study was to examine the relationship between MSE, diagnostic and clinical characteristics, and subsequent episodic memory performance in older adults. A nonprobability sample of 200 cognitively normal and older adults with mild cognitive impairment (MCI) participating in a longitudinal population-based study investigating the incidence, prevalence and risk factors for MCI completed a questionnaire about self-referent beliefs of MSE. Bandura's (1989) selfefficacy theory and the Integration Model (Whittemore, 2005) informed the descriptive study. Pearson product-moment correlations, a general linear model and a multiple linear regression analysis were conducted. The difference in MSE ratings between the cognitively normal group and the MCI group tested as a whole was significant when adjusting for age, gender and educational attainment (p < .001; ES= 0.585). The overall regression model explained 17 % of the variance of MSE (p < .001) and included age, gender, educational attainment, APOE 4 genotype, family history of dementia, cognitive diagnosis and depressive symptoms. After controlling for age and the other variables of interest, cognitive classification and depression were significant predictors of MSE. Higher MSE ratings were correlated with better episodic memory performance for both groups (r = .273, p < .001). Memory training that capitalizes on the benefits accruing from higher MSE is needed for cognitively normal older adults and older adults with MCI.

To protect and restore the biological integrity of streams, we need to be able to both detect biological degradation and infer likely causes of impairment. Managers often use biological indices to measure biological condition and detect degradation. However, the ability to detect degradation can be limited by the performance of the indices we develop. Index performance varies widely, but the sources of this variation are often unclear. In addition, although bioassessments are useful tools for detecting biological degradation, they do not identify stressors associated with impairment. My thesis research had two general goals: 1) develop statistically and ecologically robust indices to measure biological condition in Nevada streams and 2) quantify relationships between land uses, stressors, and biological condition to infer likely causes of degradation. I developed two biological indices for Nevada streams, a multimetric index (MMI) and observed to expected (O/E) taxa ratios, and determined if index performance was related to site isolation and sample evenness. The Nevada O/E indices were relatively imprecise compared with those from other regions, which likely results from low assemblage predictability associated with spatial isolation of aquatic habitats in arid regions. In contrast, the Nevada MMI was more precise than most previously developed MMIs, likely the result of using models to reduce natural variation in index scores. Sample evenness was positively associated with both O/E and MMI scores. Adjustments of index scores for sample evenness increased index precision, but also altered relative differences in index values and therefore inferences of biological impairment at specific sites. I also quantified relationships between biological condition, instream stressors, and land uses and used a weight of evidence approach to infer likely causes of degradation. Land uses such as agriculture, urbanization, and mining were associated with the spatial distributions of instream stressors, and these stressors were associated with variation in biological condition. Total dissolved solids and metal contamination were the stressors most strongly associated with biological condition. By detecting biological degradation and identifying important stressors and their potential sources, the tools I developed should help managers target conservation and restoration efforts and improve their ability to protect freshwater resources.

This dissertation is a critical examination of the relationship between sleep problems and/or disorders, particularly Obstructive Sleep Apnea (OSA) and Alzheimer Disease (AD). First, I conducted an exhaustive systematic review of existing literature, and identified gaps in research that led to specific research aims. For the first aim, I conducted the first ever-published meta-analysis examining sleep, cognitive decline and AD, providing an aggregate effect of sleep on AD. Second, focusing on OSA, I conducted a study examining OSA’s effect on longitudinal changes on AD biomarkers in cognitive normal, MCI and AD subjects, using data from the Alzheimer Disease Neuroimaging Initiative (ADNI). Lastly, I conducted a review, integrating over 3 decades of research examining OSA and cognition; OSA and subsequent cognitive decline; and OSA and AD; with particular focus in appreciating the heterogeneity of OSA and its outcomes in distinct age groups. Results and implications from my research indicate that ample evidence exists linking sleep impairments and circadian regulating mechanisms directly to clinical symptoms in AD. Sleep problems and/or disorders increases your risk of cognitive decline and AD. OSA is associated with increased AD biomarker burden over time, and effects longitudinal changes in these biomarkers, such that OSA subjects progress faster than non-OSA subjects do. OSA may be age-dependent in older adults (60 – 70 years old) and the elderly (70 years and above) and is associated with neurodegenerative diseases particularly, cognitive decline and AD. Intermittent hypoxia and sleep fragmentation are two main processes by which OSA induces neurodegenerative changes. Therefore, clinical interventions aimed at OSA, such as treatment with CPAP or dental appliances, in cognitive normal and MCI patients, could possibly slow the progression of cognitive impairment to AD.

Hearing loss and cognitive impairment are significant health problems, threatening the independent function of older adults. While there appears to be a strong relationship between the two conditions, the mechanisms underlying this association are complex and are not fully elucidated. The purpose of this secondary analysis was to explore the relationship between hearing ability and cognitive performance in older adults. In addition, this study attempted to examine the role of depressive symptoms in the relationship between hearing loss and cognitive performance. Comprehensive measures of peripheral hearing, central auditory processing and cognitive performance were utilized to examine these relationships in a sample (N = 30) of adults aged 60 years and older. The Geriatric Depression Scale (GDS) was used to assess depressive symptoms. Correlational analyses revealed a statistically significant relationship between central auditory processing and executive function. Statistically significant relationships were also observed between speed of processing and peripheral hearing as well as central auditory processing. No significant relationships were noted between depressive symptoms, hearing acuity and cognitive performance. While the correlation coefficients (r) for several of the hearing and cognitive performance measures were not statistically significant, medium effect sizes were detected, suggesting a moderate association may exist between these variables.