Dissertation

An Intergenerational Examination of Posttraumatic Stress Disorder and Intelligence

Cross Mokdad, Dorthie Sue

2014

Overview

Individuals with posttraumatic stress disorder (PTSD) perform poorer on tests of intelligence than do individuals without PTSD, but the meaning of this finding is controversial. What continues to spark debate is whether either or both variables have a causal impact on the other and whether other factors better explain group differences. One such set of factors may be intergenerational effects of trauma on both cognitive development and risk for PTSD. This dissertation is comprised of three chapters. The first chapter presents three candidate theories to explain the relationship between intelligence and PTSD, namely a social resource theory, a plasticity theory, and a heritability theory. The second chapter presents a quantitative and qualitative review of 29 cross-sectional and 9 prospective studies, demonstrating significant deficits of intelligence, with perhaps more pronounced difference in analytical and analogical reasoning in individuals with PTSD. Results suggested that intelligence may be both an influencing factor prior to traumatic exposure and be impacted following it, supporting both the heritability and the plasticity theories. The third and final chapter presents findings from a cross-sectional study of mother-child pairs, examining intergenerational influences of maternal trauma, PTSD, and parenting (i.e., child abuse potential, overreactivity, and laxness) on the relationship of intelligence to PTSD in children. Participants were 48 mothers and 55 children (29 girls, 26 boys), ages 8 to 12 years, recruited from clinic waiting rooms of a public hospital. Mothers with PTSD performed poorer on a measure of analogical reasoning but, unexpectedly, demonstrated an advantage for nonverbal recognition, even accounting for trauma and other psychopathology. For children, lower verbal intelligence was associated with more frequent symptoms of PTSD, even accounting for child trauma and psychopathology; however maternal factors (i.e., maternal intelligence, trauma, PTSD, and parenting) did not predict child outcomes. Although evidence of an intergenerational impact of intelligence on risk for PTSD was not directly observed in this study, likely due to small sample size, other studies should consider the role of parenting on the relationship between children’s intelligence and symptoms of PTSD.

• Publisher: ProQuest Dissertations & Theses
• Subject: Clinical psychology / Cognitive psychology / Developmental psychology
• ISBN: 1321341725, 9781321341720