PhD Oral Exam - Sara Matovic, Psychology

When studying for a doctoral degree (PhD), candidates submit a thesis that provides a critical review of the current state of knowledge of the thesis subject as well as the student’s own contributions to the subject. The distinguishing criterion of doctoral graduate research is a significant and original contribution to knowledge.

Once accepted, the candidate presents the thesis orally. This oral exam is open to the public.

Abstract

Abstract From Early Adversity to Midlife Vulnerability in Caregiving Mothers: Biopsychosocial Pathways Linking Adverse Childhood Experiences to Depressive Symptoms and Cardiometabolic Risk Sara Matovic, Ph.D. Concordia University, 2026 Adverse childhood experiences (ACEs), including abuse and neglect, are consistently associated with increased risk for depression and cardiometabolic disease in adulthood. Consistent with the organizational perspective on development, this dissertation examined three complementary biopsychosocial pathways through which ACEs confer risk for depressive symptoms and biomarkers associated with cardiometabolic vulnerability in a longitudinal sample of midlife caregiving mothers experiencing higher and lower chronic caregiving stress associated with raising an adolescent with or without a neurodevelopmental disability. This chronic stressor provided a context to examine stress sensitization processes in midlife using a stressor that is independent of participants’ own childhood histories. Study 1 examined a biological pathway linked to cardiometabolic risk, while Studies 2 and 3 examined interpersonal and cognitive-affective pathways linked to depressive symptoms. Study 1 found that greater ACE exposure was associated with steeper increases in leptin over 30 months, which was partially mediated by corresponding increases in waist circumference, suggesting that ACE-associated increases in central adiposity may drive leptin dysregulation in midlife. Study 2 found that greater ACE exposure was associated with lower daily capitalization, the process of sharing positive news with others and perceiving their responses as enthusiastic, which predicted reduced relationship closeness and greater depressive symptoms, forming a significant serial indirect pathway independent of relationship stress and caregiving demands. Study 3 found that lower resting respiratory sinus arrhythmia (RSA), a physiological marker of emotion regulation, amplified the association between ACEs and depressive symptoms, and that reduced perceived control and greater perseverative thinking emerged as significant mediating pathways, particularly among individuals with lower RSA. Across studies, ongoing caregiving stress amplified ACE-related associations with perceived threat and relationship stress but did not interact with ACEs to predict adipokine trajectories, positive interpersonal functioning, perceived control, or perseverative thinking, suggesting that some ACE-related processes reflect stable enduring alterations while others remain sensitive to current stressors. Together, these findings highlight the importance of biopsychosocial frameworks for understanding how early adversity shapes vulnerability to depression and cardiometabolic risk across the life course.