UT Southwestern School of Health Professions
Permanent URI for this collectionhttps://hdl.handle.net/2152.5/6691
Welcome to the UT Southwestern School of Health Profession’s electronic theses and dissertations (ETD) collection. (Note: The school was previously named the UT Southwestern School of Allied Health Sciences.)
Most UT Southwestern ETDs are subject to a default embargo period of two (2) years from the date of degree conferral. These embargoed ETDs are unavailable until the embargo expires. If you are prompted to log in and/or see a message that reads “This item is restricted”, then the ETD is still under embargo.
To verify whether an ETD is available or if you have other questions, please contact etd-utsw@utsouthwestern.edu.
Print theses and dissertations from 1943 to 2004 are located in the Library's Special Collections and Archives (Room E3.314) and are available by appointment. (Note: Former students may request a digitized copy of their work by email, but other users may submit an Interlibrary Loan request.) For more information, contact archives@utsouthwestern.edu.
Browse
Browsing UT Southwestern School of Health Professions by Author "Cullum, C. Munro"
- Results Per Page
- Sort Options
Item Analysis of Practice Effects Across Cognitive Domains in Mild Cognitive Impairment(2014-09-01) Rao, Shruthi; Lacritz, Laura; Cullum, C. Munro; Martin-Cook, KristinSerial assessments provide clinically useful information about progression of a disease. Since individuals with mild cognitive impairment are less likely to show decline in cognitive areas other than memory, it is important to analyze which domains are more susceptible to practice effects than others. The appearance of practice effects in serial assessments is a common challenge for clinicians interpreting neuropsychological tests. Detecting true change can be altered by factors such as test intervals, standardization procedures, alternate forms, respondent characteristics, and cognitive domains impaired in a clinical population. Some cognitive domains such as learning, memory, and executive functioning are known to be more susceptible to practice effects than others such as processing speed, attention, and language. Normal adults are also shown to have greater practice effects over multiple exposures than disease populations. The review supports the claim that healthy adult individuals are more likely to improve and show greater practice effects during serial assessments than clinical populations. In patients with mild cognitive impairment (MCI), domains that rely on recall and learning test rules like learning, memory, and executive functioning tend to be more susceptible to practice effects than crystallized and skill - based domains such as language, processing speed, and attention. Future research should focus on developing reliable change indices for each cognitive domain and possibly each neuropsychological test to help provide a comparison and detect true change in test scores. Studies should also focus on developing alternate equivalent forms, which would help minimize practice effects across populations.Item Do Concussion History and Gender Influence Neurocognitive Testing Performance(2016-11-21) Borque, Brandy; Silver, Cheryl H.; Cullum, C. Munro; Resch, JacobBACKGROUND: To date, the literature regarding sport concussion (SC) has concentrated primarily on male athletes. Generally, as research on female athletics has increased, there is an overall agreement that female athletes show more impairment post-injury than males. However, more data are needed to determine how SC impacts the female athlete and if that impact is influenced by factors such as age or history of prior concussion. SUBJECTS: Subjects with and without a previous history of concussion at the high school and college level were included and carefully matched for age, gender, height, and weight. After careful matching, five high school athletes with a history of prior SC were compared with five high school athletes without a concussion history, and 14 college athletes with a history of prior SC were compared with 14 matched college athletes without a concussion history. METHOD: Data for this study were acquired from a larger study conducted at the University of Texas at Arlington that examined sport concussion in high school and college athletes. Variables included previous concussion history and baseline scores from the ImPACT test. It was hypothesized that female athletes with a previous SC would show more impairment on baseline neurocognitive measures and would report greater symptom severity at baseline testing compared to athletes without a prior SC. In addition, it was hypothesized that female athletes with a previous SC at the high school level would show more impairment on baseline neurocognitive measures than college athletes with prior SC and that high school players would show greater symptom severity compared to college athletes at baseline. RESULTS: No significant differences were seen on any ImPACT baseline composite scores between athletes with and without a reported history of prior concussion. Similarly, no differences on ImPACT baseline total symptom scores were seen between athletes with concussion versus without a history of prior concussion. Finally, there were no differences on ImPACT composite or total symptom scores between college and high school athletes.Item Examining Neurological and Psychological Symptoms of Gulf War Illness Using the Minnesota Multiphasic Personality Inventory-2(2014-12-22) Hillis, George Andrew James; Cullum, C. Munro; Posamentier, Mette; Motes, Michael A.BACKGROUND: Gulf War Illness (GWI) reflects a constellation of symptoms that affect a large number of veterans from the 1990-1991 Gulf War. Reported ailments include a variety of cognitive, musculoskeletal and psychological complaints. Whereas many symptoms were originally attributed to psychological causes, chemical exposures resulting in neurological damage have since been reported. The purpose of the study was to examine self-reported psychological symptoms and profiles in GWI, with an emphasis on symptoms that may have a neurological basis. SUBJECTS: Groups were comprised of 65 Gulf War veterans with GWI (“cases”) and 31 healthy age-matched veteran controls recruited from a National Survey. The case group was divided into one of three GWI syndromes: syndrome 1 (Impaired Cognition), syndrome 2 (Confusion-Ataxia), and syndrome 3 (Central Pain). METHOD: Participants completed the Minnesota Multiphasic Personality Inventory-2 (MMPI- 2), a common self-report psychological diagnostic inventory, including the standard clinical scales, a set of restructured scales which eliminates item overlap, and a set of scales designed to assess neurologic symptoms, across cases, controls, and syndromes. RESULTS: GWI subjects displayed higher scores across all MMPI-2 scores compared to controls. Additionally, those with GWI who endorsed a larger percentage of neurological items displayed higher elevations on all other MMPI-2 scales. Within GWI syndromes, syndrome 2 (Confusion-Ataxia) endorsed the highest percentage of neurological ailments and scored higher than the other groups on all additional scales examined. DISCUSSION: Veterans with GWI displayed a nonspecific, generalized pattern of distress on the MMPI-2. While specific neurological and psychological processes were not identified, results highlight the range and severity of symptoms reported in veterans with GWI.Item ImPACT™ Performance of High School Student Athletes with ADHD(2015-08-31) Gomez, Brooke Marie; Silver, Cheryl H.; Resch, Jacob; Cullum, C. MunroBACKGROUND: To date, two studies demonstrate that adolescents with ADHD tend to perform poorer on the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT; Lovell, 2013) at baseline than do adolescents without ADHD at baseline (Elbin et al., 2013; Zuckerman, Lee, Odom, Solomon, & Sills, 2013). In an effort to replicate and extend these studies, the baseline and immediate post-concussion performance of high school athletes with and without ADHD were evaluated to identify potential differences between groups on the ImPACT’s domains. SUBJECTS: Student athletes were recruited from a private high school. Baseline testing was conducted biannually to establish pre-injury/baseline levels of individual participants. Thirty-eight students with ADHD and a matched control group of thirty-eight students without ADHD were used to test the first hypothesis. Twenty-three students with ADHD and a matched control group of twenty-three students without ADHD who sustained a concussion were used to test the second and third hypotheses. Additional analyses were performed on data from four student athletes with ADHD who sustained a concussion. METHOD: Data were used from a larger study conducted by a large public metropolitan university. Variables included demographic information and the ImPACT. All data were stored on an encrypted computer or in a locked file cabinet. RESULTS: Independent samples t-tests revealed significant differences between athletes with ADHD and non-ADHD athletes at baseline on the Impulse Control (t (74) = 2.73, p < .01) and the Total Symptoms (t(74)= 2.63, p < .05) scores of the ImPACT. A multivariate analysis of variance (MANOVA) was conducted on data from two time periods. A statistically significant difference (F(6, 39) = 2.86, p = .02; Wilks’ ? = 0.694; ?2 = .31) in ImPACT performance was found between non-concussed athletes with ADHD tested at baseline and concussed athletes without ADHD tested within 72 hours of injury (M = 1.83 days). Further analysis using independent samples t-tests found that athletes with ADHD at baseline performed significantly better than concussed athletes without ADHD tested within 72 hours of injury, on the following composites: Verbal Memory (t(44)= 2.25, p < .05), Visual Motor Speed (t(44)= 2.33, p < .05), Reaction Time (t(44)= -3.42, p < .01), and Total Symptoms (t(44)= -3.52, p < .01). No significant between-group differences were found on the Visual Memory or Impulse Control composites of the ImPACT. DISCUSSION: These findings indicate that administration of the ImPACT to individuals with ADHD is appropriate. At baseline, both groups performed similarly on Verbal Memory, Visual Memory, Visual Motor Speed and Reaction Time. However, the overlap in ADHD and concussion profiles on Impulse Control and Visual Memory warrant caution in the clinical interpretation of the ImPACT profiles of individuals with ADHD. Nevertheless, these findings suggest that the overall use of normative data within an ADHD population is appropriate, and baseline testing has values for athletes with ADHD.Item Long Term Cognitive Sequelae of Adolescent Cannabis Use in Individuals with Psychosis(2014-08-28) Shalvoy, Alexandra Miller; Ghose, Subroto; Tamminga, Carol; Cullum, C. MunroBACKGROUND: Cognitive deficits are well established in schizophrenia and there is evidence of an association between adolescent cannabis use and cognitive function in schizophrenia. This study examined the relationship between age of cannabis use and cognition in individuals within the psychosis domain, including those with schizophrenia, schizoaffective disorder and bipolar disorder with psychosis. SUBJECTS: Archival data from the University of Texas Southwestern Medical Center (UTSW) site of the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study. Participants included probands with schizophrenia, schizoaffective disorder, bipolar disorder with psychotic features, and healthy controls with and without a history of cannabis use. METHOD: The psychosis (N=97) and control (N=64) groups were divided into six groups: control with no cannabis use (CCB-; N=38), control with adolescent cannabis use (CCB+; N=16), control with late cannabis use (N=10), psychosis with no cannabis use (PCB-; N=48), psychosis with adolescent cannabis use (PCB+; N=33), and psychosis with late cannabis use (N=16). All participants completed the Brief Assessment of Cognition in Schizophrenia (BACS) neuropsychological battery, the Birchwood Social Functioning Scale, Structured Clinical Interview for DSM-IV diagnosis, Positive and Negative Symptom Scale, as well as a detailed record of patterns of substance use including age of onset, period and frequency of greatest consumption, and most recent use. RESULTS: Regarding cognitive function, this thesis found that age of cannabis use impacted the BACS total score. Specifically, the control and psychosis adolescent cannabis use groups were not significantly different in cognitive functioning. PCB+ performed better than the other psychosis groups, and CCB+ performed worse than the other control groups. Additionally, PCB+ and PCB- were significantly different, with the PCB+ performing better cognitively. DISCUSSION: There is previous evidence suggesting that individuals with schizophrenia and adolescent cannabis have less neuropsychological impairment compared to individuals with schizophrenia who do not have a cannabis use history. In this thesis, we extended these findings to psychosis as a spectrum, finding that individuals with psychosis and adolescent cannabis use had better overall cognition as measured by a brief neurocognitive test battery compared to those with psychosis and no cannabis use history.Item Predictors of Persistent Neurobehavioral Symptoms in Adolescents with Mild Traumatic Brain Injury Using a Novel Clinical Tool(2021-07-23) Wright, Brittany Nicole; Brewer-Mixon, Karen; Cullum, C. Munro; Juengst, Shannon B.; Krumwiede, Kimberly Hoggatt; Terhorst, Lauren; Wilmoth, Kristin MichellePersistent post-concussion symptoms in adolescents are non-specific and poorly understood. A small percentage of adolescents (roughly 20%) will experience persistent symptoms following mTBI that can be disruptive in many areas of daily functioning. Including measures in assessment that are specific to adolescents but capture symptoms beyond injury may lead to more insight as to why some adolescents experience persistent symptoms. Moreover, identifying predictors of persistent symptoms could aid in management and evaluation of symptoms. The current set of studies was designed to validate a measurement tool for adolescents and identify predictors of persistent symptoms in a cohort of adolescents with mTBI. Study 1 was designed to further validate a tool (the BAST-A), which assesses persistent emotional and behavioral symptoms in adolescents. Another aim was to develop ordinal to continuous normed scores to aid in clinical interpretation. When assessing the psychometric indicators of the tool, both the Negative Affect and Fatigue and Executive and Social Function subscales performed well. However, the Risk Behaviors subscale performed poorly in this sample of adolescents with sports-related concussion. Specifically, Risk Behaviors was not able to distinguish different severity levels in the sample. Results from this study suggest further psychometric validation of the BAST-A in adolescents with mTBI. The aim of Study 2 was to utilize the ordinal to continuous normed scores in the first study to assess if a combination of predictors was associated with persistent neurobehavioral symptoms in adolescents with mTBI. A combination of pre-injury and injury predictors was significantly associated with self-reported Negative Affect and Fatigue symptoms (F (8,93) =6.09, p<.001) and Executive and Social Function symptoms (F (8,93) = 2.18, p=.036). Due to limitations within the Risk Behaviors subscale, binary (Yes/No) outcomes were used. A combination of pre-injury and injury factors was also significantly associated with self-reported Risk Behaviors [χ2(8) = 18.84, p=.016]. Across subscales, total number of recent life stressors remained a significant predictor of persistent symptoms. The results from this study indicated that a combination of injury-related and personal factors is predictive of persistent symptoms and that recent life stressors contribute to the experience of these symptoms.Item Relationship Between Exercise and Cognitive Functioning in Breast Cancer Survivors Following Chemotherapy(2013-05-17) Antony, Merlyn; Kendall, Jeffrey; Cullum, C. Munro; Chiu, Chung-YiBACKGROUND: A growing body of research suggests that individuals who undergo chemotherapy for treatment of cancer experience adverse changes in cognitive functioning as a side effect of treatment. While there is not yet a known remedy for such effects, exercise has shown to improve cognitive functioning in individuals within other clinical populations. Therefore, the purpose of this current study is to examine whether any relationships exist between self-reported post-chemotherapy exercise and cognitive functioning. SUBJECTS: The sample consisted of sixty female breast cancer survivors between the ages of 38-71. All participants had been diagnosed with stage I, II, or III breast cancer and had completed chemotherapy between three months to two years prior to their study visit. METHOD: Participants completed a self-report measure of post-chemotherapy exercise behavior and were administered a battery of neurocognitive tests to measure cognitive functioning. Subjects were categorized into one of three exercise groups based on their total exercise score (LSI): sedentary (LSI < 14), moderately active (LSI = 14-23), or active (LSI > 24). Mean scores on cognitive tests between exercise groups were compared to determine whether significant differences existed between groups both before and after controlling for IQ. Additionally, a hierarchical multiple regression was performed to determine how much of the variance in cognitive test scores could be explained by the following predictors: age, education, IQ, anxiety, depression, and exercise. RESULTS: Only three test scores (CVLT, Digit Span Backward, and Digit Symbol Coding) showed significant differences between exercise groups. Before controlling for IQ, CVLT (F=7.40, p=.001) and Digit Span Backward (F=3.01, p=.057) displayed significant differences between groups. After controlling for IQ, CVLT (F=4.19, p=.012), Digit Span Backward (F=5.98, p=.004), and Coding (F=3.05, p=.055) displayed significant differences. Predictors explained a small portion of the variance in cognitive test scores. DISCUSSION: Only three out of seven cognitive test scores demonstrated differences between exercise groups. Even among those tests that showed differences, higher levels of exercise were not consistently associated with better performance. In some cases, a moderate level of exercise seemed to have an optimal effect with regard to cognitive performance, suggesting the possibility of a dosing effect of exercise. Overall these findings suggest that a possible relationship may exist, but additional research is warrantedItem Use of Cognitive Screening and the Influence of Psychosocial Variables in Identification of Cognitive Impairment in MS(2013-05-17) Ritter, Ashley Reyes; Lacritz, Laura H.; Hynan, Linda S.; Cullum, C. MunroBACKGROUND: The purpose of this project is to examine the potential of abbreviated cognitive screening to identify patients with clinically significant cognitive dysfunction. A secondary goal is to examine relationships between cognitive functioning and psychosocial factors of disease. SUBJECTS: The study includes 94 subjects with a Demyelinating disease [M age = 45.04 (11.08); M education = 15.40 (2.13)] who were referred to the University of Texas Southwestern Medical Multiple Sclerosis Clinical Center and Multiple Sclerosis Program and signed informed consent for a larger study on cognition in multiple sclerosis and demyelinating disease. METHOD: Subjects completed a screening battery (JoL, 9HPT, PASAT, SDMT-Oral, and T25FW) at visit one and a larger cognitive assessment within 4 weeks of visit one, which was used to divide subjects into impaired and non-impaired groups. Linear regression was used to assess which tests on the screening battery predicted impairment on the longer battery. Associations between psychosocial factors of depression, fatigue, and sleepiness were examined in relation to cognitive performance. The relationship between depression and objective versus subjective cognitive performance was also examined. RESULTS: The PASAT (p = .001) was the only measure in the screening battery that predicted group membership, with correct classification of 76% of subjects using a cut score of T ² 38. Depression (QIDS-SR) was significantly correlated with self-reported cognitive dysfunction (MSNQ) (r = .57; p = <.001) but only modestly associated with the four measures on the screening battery (r = -.17 to .25). Those who endorsed depressive symptoms performed lower on JoL(p = .003), PASAT (p = .015) and SDMT (p = .023). Level of fatigue was associated with cognitive performance, as significant mean differences were found on all screening battery measures in high versus low fatigue groups. There was no impact of sleepiness on cognition. DISCUSSION: Complex attention was the most sensitive measure for predicting cognitive impairment on a more comprehensive battery and may be a good screening tool in identifying who might benefit from more detailed testing. Higher levels of depression and fatigue significantly impacted test performance and highlight important areas for screening and treatment, while daytime sleepiness had no effect.