Theses and Dissertations from UMD
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New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a give thesis/dissertation in DRUM
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Item The Validity and Comparison of Two Affiliation Tasks in Schizophrenia(2016) Garcia, Cristina Phoenix; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Negative symptoms are related to worse psychosocial functioning in schizophrenia. The current study evaluates two behavioral affiliation tasks—the video-based Social Affiliation Interaction Task (SAIT) and the in-vivo Conversation Task (CT)—and explores whether behavioral ratings of social affiliation are associated with negative symptoms and community functioning. Participants, 20 with schizophrenia/schizoaffective disorder (SZ) and 35 healthy controls (HC), completed both tasks and measures of negative symptoms and functioning. SZ evidenced lower behavioral affiliation on the SAIT compared to HC. There were no group differences in behavioral affiliation on the CT. Within groups, behavioral affiliation was not correlated between tasks or with symptoms and functioning. Across groups, behavioral affiliation from the SAIT was correlated with symptoms and functioning. Post hoc analyses revealed higher ratings of positive facial expression and valence in the CT for HC compared to SZ. Results suggest that the method of assessing behavioral affiliaton may influence research findings.Item Analysis of Gamma-Band Auditory Responses in Schizophrenia(2015) Walsh, Benjamin Bryan; Simon, Jonathan Z; Electrical Engineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Schizophrenia is a debilitating mental illness that affects 1% of the general population. One characteristic symptom is auditory hallucinations, which is experienced by almost all patients sometime in their lifetime. To investigate differences in auditory response in general, 50 schizophrenic patients and 50 age and sex-matched healthy controls were presented with auditory click trains at 40 Hz. Responses are recorded using electroencephalography (EEG). Magnitude and phase of responses at 40 Hz are computed using Gabor filters. Supporting previous literature, a significant difference in inter-trial phase coherence (ITC) and overall power is found between patients and controls, in particular near stimulus onset. Additionally, this study also investigated inter-subject phase coherence (ISC). This study finds that ISC is in fact higher for patients, in particular near stimulus onset. One possible explanation is that while healthy controls develop a preferred phase for perception, schizophrenic patients exhibit phase that is primarily stimulus-driven.Item Social Emotional Memory and Negative Symptoms in Individuals with Schizophrenia(2015) Bradshaw, Kristen Renee; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)The current study investigated social and nonsocial emotional memory in schizophrenia, the relation of impairments in the recall of positive stimuli to increased negative symptoms, and the mediating role of defeatist performance beliefs. Twenty-three individuals with schizophrenia and twenty-four healthy controls completed clinical symptom interviews, social and nonsocial laboratory emotional memory tasks, and a measure of dysfunctional attitudes. Results indicated that on a social affective learning task, in comparison to controls, the schizophrenia participants were impaired in their ability to exhibit minimal affective learning of positive pairings. Defeatist performance beliefs did not mediate the relation between recall of positive stimuli and experiential negative symptoms. These findings suggest that it is primarily in the social domain that we see deficits in emotional memory in schizophrenia, and that this impairment in the ability to learn positive social associations may be linked to decreased motivation to engage in social, vocational, and recreational activities.Item The Valuation of Social Reinforcement in Schizophrenia(2015) Catalano, Lauren Theresa; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Facial affect perception impairments impede social functioning in schizophrenia. What remains unknown is how individuals with schizophrenia assign value to pleasant facial expressions that typically motivate social affiliation. The current study adapted a matching pennies game (Shore & Heerey, 2011) to assess the subjective value of social feedback in terms of money. Individuals with schizophrenia and controls were instructed to choose the same side of a coin as six computerized partners, each of whom provided different rates of monetary feedback and types of social feedback. In a later test phase, participants chose which partner to play from amongst pairs of partners. Among participants who appropriately learned task contingencies, individuals with schizophrenia failed to use genuine smiles to motivate choices to the same extent as controls; however, money was equally valued. These findings suggest that there is a reduced sensitivity to social rewards in schizophrenia.Item Parsing Hedonic Capacity in Schizotypy: A Multi-Method Assessment of Consummatory and Anticipatory Pleasure(2012) Wilson, Amy; Blanchard, Jack J.; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)This study was an attempt to examine anhedonia (or a reduced capacity to experience pleasant emotion) in individuals with elevated schizotypy. Anhedonia deficits in schizophrenia have been well-documented in studies utilizing self-report and clinician interviews; however, research has also shown that when presented with emotionally evocative stimuli, individuals with schizophrenia respond in a normative manner. One explanation for these paradoxical findings is that individuals with schizophrenia do not lack the capacity to experience pleasure (termed consummatory pleasure), but instead have a deficit in anticipating how pleasurable an event will be outside of the context of an immediately experienced event (known as anticipatory pleasure). Research is beginning to indicate that anticipatory pleasure deficits are evident in the schizophrenia population; however, a number of confounding variables are associated with this population which render conclusions about hedonic capacity difficult. A complimentary approach to examining individuals with schizophrenia is to identify nonclinical individuals with elevations in traits that are considered to be within the schizophrenia spectrum, namely, schizotypal traits. Utilizing the schizotypy concept first described by Paul Meehl, this study examines hedonic capacity using a multi-method approach (consisting of self-report, clinical interview, and an emotionally evocative stimulus) in schizotypy within a sample of undergraduate college students. Results were able to confirm that individuals with schizophrenia spectrum psychopathology both self-report and are rated as experiencing impairments in the ability to anticipate future pleasure. No group differences in anticipatory pleasure were identified on the laboratory stimulus, raising questions about our understanding of the nature of the anticipatory pleasure deficit in schizophrenia spectrum psychopathology.Item An Initial Assessment of the Convergent Validity of the Negative Symptom Rating Scale: The Relationship Between Behavioral Codings of Expressed Facial Affect and Clinical Ratings of Blunted Affect(2009) Baker, Bryann Renee; Blanchard, Jack J.; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Schizophrenia is a severe mental illness that represents a significant public health burden. No treatments are FDA approved for negative symptoms of schizophrenia, primarily because there is no valid, reliable measure for negative symptoms. A new negative symptom measure, the Negative Symptom Rating Scale (NSRS), is in the initial phases of validation. The current study assesses the convergent validity of the scale by examining the relationship between the NSRS and expressed facial affect. The study also sought to clarify the relationship between expressed facial affect and functioning. The results revealed a significant relationship between expressed facial affect and the NSRS subscale of blunted affect, as predicted. However, there was not a significant relationship between expressed facial affect and functioning. These results provide initial evidence for the convergent validity of the scale. Currently, there is an ongoing research study to further assess the reliability and validity of the NSRS.Item Susceptibility to Smoking and Nicotine Dependence in Schizophrenia(2009) Saperstein, Alice Meredith; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Evidence suggests that high nicotine dependence observed in schizophrenia is related to its core neuronal deficits such as abnormalities in neural synchronization and sensory gating. Some of these neuronal deficits are shown to mark schizophrenia liability, raising the possibility that the increased nicotine dependence in schizophrenia is related to its etiological factors. This study sought to investigate mechanisms of increased vulnerability to smoking and nicotine dependence in schizophrenia. The individual and interacting effects of familial vulnerability factors, neurophysiological function, and resting cortical oscillatory activity (i.e. resting EEG power) were examined. The study sample was composed of four groups including outpatients with schizophrenia, first-degree relatives of patient index probands, healthy comparison control subjects from the community, and first-degree relatives of control probands. The resulting data demonstrated a pattern of more persistent nicotine use and greater dependence among those with schizophrenia relative to non-psychiatric comparison controls. Persistent smoking was also demonstrated to be highly heritable across groups with no discernable difference in the extent to which smoking is familial in those affected or unaffected by schizophrenia. With respect to resting oscillatory activity, analyses failed to find diagnostic group differences in EEG power for the alpha, beta, and gamma frequency bands and, unlike other substances of abuse, past and present nicotine use did not have a reliable effect on power in the beta frequency band. Rather, power in the gamma frequency band was significantly associated with smoking status. Furthermore, smoking was uniquely related to neurophysiological processes in probands with schizophrenia, suggesting that smoking status should be assessed in any study of information-processing dysfunction in this population. When all putative susceptibility factors were considered together, diagnosis of schizophrenia and family history of smoking best captured what may be characterized as an underlying (i.e. neurobiological) vulnerability to nicotine dependence, rather than circumscribed indices of electrophysiological functioning. Future studies might be implemented to refine the association between smoking and indices of electrophysiological function and, importantly, relate diagnostic or electrophysiological susceptibility factors to mediating processes and observable behaviors associated with aberrant patterns of nicotine use and dependence in persons with schizophrenia.Item Racial Differences in Psychotic-like Experiences: A Study of Schizotypy in African Americans and Caucasians(2007-08-03) Adams, Kimberly Anne; Blanchard, Jack J.; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)A considerable literature has long indicated that African Americans consistently receive more clinical diagnoses of psychosis than their Caucasian counterparts although higher rates of schizophrenia in African Americans have not been reliably documented. Prior studies are limited in that while many have found elevations in psychotic symptoms and schizophrenia diagnoses in African Americans patients, it is unclear whether these race differences indicate true rates of psychosis or whether other mechanisms such as lowered medication compliance and limited access to treatment might be complicating these findings. Further, comparisons between racial groups in studies of psychosis-proneness have focused primarily on mean group differences in overall psychotic symptoms. While helpful in establishing the existence of symptom differences in racial groups, these finding do not provide more qualitative information regarding the specific nature of these differences. It can therefore be suggested that a comprehensive understanding of the role of race in schizophrenia remains elusive. The goal of the current study was to extend the available research on race differences in the experience of psychotic-like experiences by addressing the following hypotheses in a sample of putative schizotypes (social anhedonics): 1) Social anhedonics will report more psychotic-like symptoms and experiences than controls, regardless of race, 2) Psychotic-like experiences will be more prevalent in socially anhedonic African Americans compared to socially anhedonic Caucasians, and 3) socially anhedonic African Americans will report more psychotic-like experiences with religious and paranoid themes than socially anhedonic Caucasians. Possible reasons for differential symptom expression will be explored, followed by assessment and treatment implications. Finally, suggestions for future directions of study will be discussed.Item Smoking and Neurophysiological Markers of Information Processing in Schizophrenia(2007-05-25) Saperstein, Alice Meredith; Blanchard, Jack J.; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)The primary aim of this study was to compare patterns of nicotine consumption among patients with schizophrenia and a matched community control sample. Assessments included self-report and biological indexes of nicotine use as well as behavioral measures of smoking topography. Secondarily, this study tested the hypothesis that aspects of nicotine consumption are more closely associated with abnormalities in sensory gating and eye tracking performance among smokers with schizophrenia. Results from 50 patient and 10 healthy control smokers provided some evidence to support the primary hypothesis; biological indexes provided the most robust evidence that patients with schizophrenia extract more nicotine from smoking cigarettes than controls. Both groups demonstrated significant relationships between measures of nicotine dependence and neurophysiological functions. Patterns of results suggest that patients are less able to regulate smoking behaviors or efficiently utilize nicotine to enhance information processing. Additional factors likely contribute to smoking phenomena observed among patients with schizophrenia.Item Experience and Expression of Emotion in Social Anhedonia: An Examination of Film-Induced Social Affiliative State in Schizotypy(2006-08-02) Leung, Winnie; Blanchard, Jack; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Social anhedonia is an important feature of schizophrenia and it is a promising indicator of schizotypy. Although social anhedonia is defined as an affective construct (less pleasure derived from social encounters), little is actually known about the affective correlates of social anhedonia. Prior laboratory research is limited in that no prior study has used affiliative social stimuli in examining affective reactions associated with anhedonia. This study sought to extend prior research through an examination of the expression and experience of emotion in social anhedonics by using a novel social affiliative film stimulus. After screening a large sample of female undergraduate students (N = 1,085), a cohort of psychometrically identified social anhedonics (n = 34) and normally hedonic controls (n = 45) participated in laboratory assessments involving trait affectivity, self-reported dispositional emotional expressiveness, and the expression and experience of emotion in response to neutral, non-affiliative (i.e., comedy) and affiliative film clips. Results showed that social anhedonics have lower trait positive affect compared to controls, but there were no group differences in trait negative affect. At baseline, social anhedonics reported lower state positive affect and less warmth and affection compared to controls, but there were no group differences in state negative affect. Social anhedonics also reported the disposition to be less expressive. Consistent with their reports of attenuated emotional experience and expression outside of the laboratory, social anhedonics reported less positive affect and displayed less facial expressions in response to affect eliciting films in the laboratory. Social anhedonics, however, did not report less warmth and affection across the films as compared to controls. Additionally, social anhedonics did not report less positive emotions or warmth and affection in response to the affiliative film, as compared to the non-affiliative (i.e., comedy) film. Implications and study limitations are discussed.