Theses and Dissertations from UMD
Permanent URI for this communityhttp://hdl.handle.net/1903/2
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
More information is available at Theses and Dissertations at University of Maryland Libraries.
Browse
4 results
Search Results
Item Functional Neuroimaging of the Social Regulation of Emotion in Schizophrenia(2016) McCarthy, Julie McCarthy; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Negative symptoms in schizophrenia are characterized by deficits in normative experiences and expression of emotion. Social anhedonia (diminished pleasure from social experiences) is one negative symptom that may impact patients’ motivation to engage in meaningful social relationships. Past research has begun to examine the mechanisms that underlie social anhedonia, but it is unclear how this lack of social interest may impact the typically positive effects of social buffering and social baseline theory whereby social support attenuates stress. The present pilot study examines how social affiliation through hand holding is related to subjective and neural threat processing, negative symptoms, and social functioning. Twenty-one participants (14 controls; 7 schizophrenia) developed social affiliation with a member of the research staff who served as the supportive partner during the threat task. Participants displayed greater subjective benefit to holding the hand of their partner during times of stress relative to being alone or with an anonymous experimenter, as indicated by self-reported increased positive valence and decreased arousal ratings. When examining the effects of group, hand holding, and their interaction on the neurological experience of threat during the fMRI task, the results were not significant. However, exploratory analyses identified preliminary data suggesting that controls experienced small relative increases in BOLD signal to threat when alone compared to being with the anonymous experimenter or their partner, whereas the schizophrenia group results indicated subtle relative decreases in BOLD signal to threat when alone compared to either of the hand holding conditions. Additionally, within the schizophrenia group, more positive valence in the partner condition was associated with less severe negative symptoms, better social functioning, and more social affiliation, whereas less arousal was correlated with more social affiliation. Our pilot study offers initial insights about the difficulties of building and using social affiliation and support through hand holding with individuals with schizophrenia during times of stress. Further research is necessary to clarify which types of support may be more or less beneficial to individuals with schizophrenia who may experience social anhedonia or paranoia with others that may challenge the otherwise positive effects of social buffering and maintaining a social baseline.Item Taxometric Analysis of Negative Symptoms in An International Sample of Ten Countries(2011) Wilson, Amy; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Negative symptoms have emerged as a replicable factor of symptomatology within schizophrenia. Although rating scales provide assessments along dimensions of severity, categorization of a negative symptom subtype is typically concluded. Despite an accumulation of findings that support categorical conceptualization, the data are also consistent with a dimensional-only model where negative symptom subtypologies simply reflect an extreme on a continuum of severity. Previous studies (Blanchard, et al, 2005) have used taxometric statistical methods to confirm the existence of a negative symptom subtype; however, the nature of taxometric methods requires replication (Waller & Meehl, 1998). The current investigation is a taxometric analysis of the World Health Organization Ten-Country Study of Schizophrenia. Data from a subset of 694 individuals were analyzed using the taxometric methods of maximum covariance analysis (MAXCOV) and mean above minus below a cut (MAMBAC) and a latent class with a base rate of approximately .14 - .16 was identified.Item The Negative Symptom Rating Scale: Initial Evaluation of Reliability and Validity(2009) Forbes, Courtney Brynn; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Negative symptoms in schizophrenia are a major determinant of the social and occupational impairments that characterize the disorder, as well as a significant source of distress for caregivers, and predictors of poor long-term outcome. Despite the compelling evidence for the clinical relevance of negative symptoms, this domain of the illness remains inadequately addressed by current pharmacotherapy and psychotherapy. As identified at the NIMH-MATRICS Consensus Development Conference on Negative Symptoms, a significant barrier to progress in the treatment of this symptom domain is the current lack of an adequate measure for assessment of negative symptoms (Kirkpatrick et al., 2006). It was in response to this need that the NIMH-MATRICS Negative Symptom Workgroup developed a new measure, the Negative Symptom Rating Scale (NSRS). The current study provided the first evaluation of the psychometric properties of the newly developed NSRS, including the inter-rater agreement and internal consistency of the NSRS scales, and assessed convergent and discriminant validity. The results of this initial psychometric evaluation of the NSRS are generally quite encouraging, and provide information that has helped inform data-driven modifications to the measure for upcoming validation studies. With regards to reliability, the NSRS demonstrated adequate internal consistency for the scale as a whole, and for three of the five subscales. The results indicated that the Asociality and Avolition subscales warrant further revisions or modifications to improve internal consistency. Additionally, three of the five subscales were found to have good to excellent interrater reliability, with the Avolition and Alogia subscales falling in the fair range. Results generally demonstrated adequate convergent validity between the NSRS and other measures of negative symptoms, namely the SANS and the BPRS Anergia subscale. Additionally, results indicated general convergence between clinician-rated anhedonia using the NSRS and self-reported anhedonia as measured by the TEPS. Finally, the NSRS showed discrimination from ratings of psychotic and depressive symptoms. The results of the present study point to areas in which revisions are necessary, and has provided valuable information that is necessary for making revisions and modifications to the measure prior to larger scale evaluation.Item Refining the Psychometric High-Risk Paradigm: Examining Negative Symptom Traits for the Identification of Schizotypy(2004-02-10) Adams, Kimberly A; Blanchard, Jack J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Research supports social anhedonia's significance as a schizotypy indicator. However, social anhedonia is only one of several negative symptoms demonstrating an important relationship with premorbid functioning, medication response, and prognosis in schizophrenia. Despite these findings, the psychometric assessment of schizophrenia has focused primarily on social anhedonia. Negative symptom research indicates that avolition, apathy, and diminished emotional expression might be useful to include as potential schizotypy indicators. This thesis examined the relationship between social anhedonia and other negative symptom-related traits, in a college sample using factor analysis and taxometric analyses. Social anhedonia loaded on the same factor as diminished emotional expression and (low) positive affect and this factor was independent of a factor comprised of positive symptom traits (perceptual aberrations and magical ideation). Despite the strong relationship between social anhedonia and the negative symptom traits, these other measures were not associated with the taxon identified by the RSAS.