A Discordant Monozygotic Twin Design Shows Blunted Cortisol Reactivity Among Bullied Children

Isabelle Ouellet-Morin, Andrea Danese, Lucy Bowes, Sania Shakoor, Antony Ambler, Carmine M. Pariante, Andrew S. Papadopoulos, Avshalom Caspi, Terrie E. Moffitt, Louise Arseneault

Research output: Contribution to journalArticle (Academic Journal)peer-review

90 Citations (Scopus)


Objective: Childhood adverse experiences are known to engender persistent changes in stress-related systems and brain structures involved in mood, cognition, and behavior in animal models. Uncertainty remains about the causal effect of early stressful experiences on physiological response to stress in human beings, as the impact of these experiences has rarely been investigated while controlling for both genetic and shared environmental influences. Method: We tested whether bullying victimization, a repeated adverse experience in childhood, influences cortisol responses to a psychosocial stress test (PST) using a discordant monozygotic (MZ) twin design. Thirty pairs (43.3% males) of 12-year-old MZ twins discordant for bullying victimization were identified in the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally representative 1994-1995 cohort of families with twins. Results: Bullied and nonbullied MZ twins showed distinct patterns of cortisol secretion after the PST. Specifically, bullied twins exhibited a blunted cortisol response compared with their nonbullied MZ co-twins, who showed the expected increase. This difference in cortisol response to stress could not be attributed to children's genetic makeup, their familial environments, pre-existing and concomitant individual factors, or the perception of stress and emotional response to the PST. Conclusion: Results from this natural experiment provide support for a causal effect of adverse childhood experiences on the neuroendocrine response to stress. J. Am. Acad. Child Adolesc. Psychiatry, 2011;50(6):574-582.

Original languageEnglish
Pages (from-to)574-582
Number of pages9
JournalJournal of the American Academy of Child and Adolescent Psychiatry
Issue number6
Publication statusPublished - Jun 2011


Dive into the research topics of 'A Discordant Monozygotic Twin Design Shows Blunted Cortisol Reactivity Among Bullied Children'. Together they form a unique fingerprint.

Cite this