Abstract
By adulthood, 25%- 30% of individuals with 22q11.2 deletion syndrome (22qDS) develop a psychotic disorder, often schizophrenia, and it is not understood why. Given the known genetic etiology of this disorder and the greatly elevated risk for development of schizophrenia, this group offers the possibility of defining a seemingly homogenous maturational pathway to psychosis. Neurocognitive deficits have been increasingly recognized as an important dimension of schizophrenia, particularly in the executive domain. Thus, we assessed multiple aspects of executive cognition in 22qDS, in order to: 1) characterize performance across this domain as compared to age-matched healthy controls; and 2) determine whether executive function performance is significantly predictive of positive and negative psychotic symptoms in 22qDS above and beyond non-verbal functioning. We assessed psychomotor speed and mental flexibility (Trails-B), working memory (Letter-Number Sequencing: LNS) and D-KEFS verbal fluency. Psychotic symptomatology was measured using scores obtained from the Structured Interview for Prodromal Syndromes (SIPS). 22qDS patients (N= 48, mean age: 15.23) showed impairment relative to healthy controls (N= 37, mean age: 14.97) on all measures of executive functioning. Regression analysis revealed that executive deficits are predictive of positive psychological symptomatology above and beyond non-verbal deficits. Specifically, D-KEFS verbal fluency added meaningfully to the prediction of positive psychiatric symptoms. Given this significant prediction it is suggested that executive function may be an important domain for providing information about the development of psychosis.
LLU Discipline
Clinical Psychology
Department
Psychology
School
School of Behavioral Health
First Advisor
Hartman, Richard E.
Second Advisor
Bearden, Carrie E.
Third Advisor
Jenkins, Louis E.
Fourth Advisor
Vermeersch, David
Degree Name
Doctor of Philosophy (PhD)
Degree Level
Ph.D.
Year Degree Awarded
2015
Date (Title Page)
12-2015
Language
English
Library of Congress/MESH Subject Headings
Psychotic Disorders; Schizophrenia; Regression Analysis
Subject - Local
22qDS; Deletion Syndrome; Genetic Etiology; Structured Interview for Prodromal Syndromes
Type
Dissertation
Page Count
62
Digital Format
Digital Publisher
Loma Linda University Libraries
Copyright
Author
Usage Rights
This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.
Recommended Citation
Bello, Chinonyere Kemdirim, "Executive Dysfunction is Predictive of Clinical Symptomatology in 22q11.2 Deletion Syndrome" (2015). Loma Linda University Electronic Theses, Dissertations & Projects. 193.
https://scholarsrepository.llu.edu/etd/193
Collection
Loma Linda University Electronic Theses and Dissertations
Collection Website
http://scholarsrepository.llu.edu/etd/
Repository
Loma Linda University. Del E. Webb Memorial Library. University Archives