Date of Conferral
Doctor of Psychology (Psy.D.)
Advancements in neuroimaging techniques afford researchers the opportunity to examine the actual brains of living persons, which exponentially contributes to new insights regarding brain and behavior phenomena. However, empirical studies investigating stress and the hippocampus attend primarily to adult populations - less on children and adolescents. Covariates such as the type of trauma, the duration and severity of the abuse, genetic predispositions, gender, poverty, and age often present as confounding factors that muddle the attempts to establish linkages between interpersonal, environmental, and neurobiological correlates. Although researchers primarily agree that traumatic early life stress (TELS) has some impact on early brain development, there is a lack of consensus around specific causes and the strength of influence. Tenets from Charcot's trauma theory and Selye's general adaptation syndrome organized the development of a meta-analysis which carefully examined the relationship between TELS and aberrant hippocampal development. Study selection was based on PRISMA standards which provide a template of a 27-item qualitative checklist for the writing and reviewing of research using secondary data sources. Criteria for inclusion resulted in 22 studies identified for preliminary analysis and 9 for the final report. The analysis revealed a vast range in individual study effect sizes (d = 0.000 to -1.892). The cumulative analysis of p values ranged from p = .005 (random effects) to p < .001 (fixed effects) indicated a relationship between TELS and hippocampal development existed and underscored the necessity for researchers to shift more attention and resources to how covariates influence effect size differences.
Johnson, Sharon, "Traumatic Early Life Stress in the Developing Hippocampus: A Meta-Analysis of MRI Studies" (2020). Walden Dissertations and Doctoral Studies. 8927.