Date of Award
2023
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Psychology
Abstract
One of the core features of schizophrenia is the remarkably stable cognitive deficits. Research consistently finds that individuals with schizophrenia demonstrate significant deficiencies in attention, working memory, verbal learning and memory, and executive functioning. Though cognitive deficits in schizophrenia have been widely investigated, research on these deficits as potential endophenotypes in those with schizotypy is variable. Even more so, the differentiation in cognitive deficits among positive, negative, and disorganized schizotypes is entirely lacking. The present study investigates whether individuals psychometrically identified to be at risk for developing a schizophrenia related illness (SRI) demonstrate deficits in neurocognition compared to healthy matched controls (MC) and evaluates differences in neurocognitive performance between schizotype groups. Neurocognitive performance was measured using the Penn Computerized Neurocognitive Battery (CNB), and schizotype group membership was determined by scores on the Multidimensional Schizotypy Scale (MSS). The final sample included 96 participants; of this sample, 48 were classified as MC, 14 as positive schizotypes, 24 as negative schizotypes, and 27 as disorganized schizotypes. It was hypothesized that schizotypes would demonstrate greater overall cognitive deficits, with greater deficits in episodic memory tasks. Disorganized schizotypes were predicted to have greater neurocognitive deficits as compared to other schizotypes. It was hypothesized that positive schizotypes would demonstrate better performance on tests of attention and executive control. Finally, it was predicted that negative schizotypes would demonstrate slower response times across all tasks. Independent means t -tests were completed to determine if there were significant differences in performance on neurocognitive tests. Results and implications of the current study are discussed in the context of endophenotype research. Furthermore, this study calls for better collaboration between researchers and clinicians as well as redefinition of the ultimate goal of schizotypy research.
Recommended Citation
Roop, Samantha M., "Neurocognitive Indicators Of Schizophrenia Liability In Positive, Negative, And Disorganized Schizotypes" (2023). All-Inclusive List of Electronic Theses and Dissertations. 2003.
https://scholars.indianastate.edu/etds/2003