Doctoral Dissertation Research: The Role of Cortisol and Inflammation in Dysregulated Stress Responses

This doctoral dissertation project uses evolutionary and endocrinological approaches to examine factors underlying post-traumatic stress disorder (PTSD) and better understand why some individuals develop PTSD while others exposed to the same stressor do not. The project leverages longitudinal data for a group of individuals who had stress hormone measurements taken during childhood and then as adults, including after a natural disaster. By pairing previously collected data with new biomarker measurements, the project tests whether early physiological signatures relate to later vulnerability or resilience. These findings advance evolutionary models of PTSD, recognizing multiple pathways that underlie symptoms. The project advances the use of biotechnology for collecting detailed physiological data and can inform novel interventions targeting the biological processes most relevant to each individual’s symptoms. The investigator leverages pilot data for individuals who were juveniles in the 1980s and who experienced Hurricane Maria in 2017 as adults, finding that specific diurnal cortisol profiles as children were associated with individuals who reported PTSD symptoms after the hurricane. The project expands this work to address how cortisol profiles change before and after a stress event, and how contemporary physiological markers, including inflammatory biomarkers, map onto distinct PTSD symptom clusters. The project uses a 72-hour continuous monitoring protocol with advanced biosensors to capture cortisol, melatonin, IL-6, and TNF-α in three-minute intervals, and compares these data to psychological assessments of PTSD symptoms. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.