J Psychiatry Neurosci 2012;35(6):370-7
Veronika Engert, PhD; Simona I. Efanov, MSc; Katarina Dedovic, BSc; Annie Duchesne, MSc; Alain Dagher, MD, PhD; Jens C. Pruessner, PhD
Engert, Efanov, Dedovic, Duchesne, Pruessner — Department of Psychiatry, Douglas Mental Health University Institute; Engert, Dagher — Montreal Neurological Institute; Pruessner — McGill Centre for Studies in Aging, Faculty of Medicine, McGill University, Montréal, Que.
Background: In the past decade, a body of animal and human research has revealed a profound influence of early-life experiences, ranging from variations in parenting behaviour to severe adversity, on hypothalamic-pituitary-adrenal axis regulation in adulthood. In our own previous studies, we have shown how variations in early-life parental care influence the development of the hippocampus and modify the cortisol awakening response.
Methods: In the present study, we investigated the influence of early-life maternal care on cortisol, heart rate and subjective psychological responses to the repeated administration of a psychosocial laboratory stressor in a population of 63 healthy young adults. Low, medium and high early-life maternal care groups were identified using the Parental Bonding Instrument.
Results: Controlling for the effect of sex, we found an inverted u-shaped relation between increasing levels of maternal care and cortisol stress responsivity. Specifically, overall and stress-induced cortisol levels went from below normal in the low maternal care, to normal in the medium care, back to below normal in the high maternal care groups. We found no group differences with respect to heart rate and subjective psychological stress measures. Whereas low and high maternal care groups exhibited similarly low endocrine stress responses, their psychological profiles were opposed with increased levels of depression and anxiety and decreased self-esteem in the low care group.
Limitations: Sex was unequally distributed among maternal care groups, whereby the number of men with low maternal care was too small to allow introducing sex as a second between-group variable.
Conclusion: We discuss the potential significance of this dissociation between endocrine and psychological parameters with respect to stress vulnerability and resistance for each maternal care group.
Submitted Jan. 27, 2010; Revised June 16, 2010; Accepted June 22, 2010.
Acknowledgments: This research was supported by a grant from the German Research Foundation (DFG) to Dr. Engert (EN 859/1-1), and by grants from the Canadian Institutes of Health Research (CIHR #81143) and the Natural Sciences and Engineering Research Council of Canada (#249996) to Dr. Pruessner. Dr. Pruessner holds a CIHR New Investigator Award. We thank I. Efanov, L. Schenk, A. Szostek and S. Wesemann for their contribution to data collection.
Competing interests: None declared.
Contributors: Drs. Engert, Dagher and Pruessner designed the study. Drs. Engert and Pruessner and MMs. Efanov and Duchesne acquired the data, which Drs. Engert and Pruessner and Ms. Dedovic analyzed. Drs. Engert and Pruessner wrote the article. All authors reviewed the article and approved its publication.
Correspondence to: Dr. J.C. Pruessner, McGill Centre for Studies in Aging, 6825 LaSalle Blvd., Montréal QC H4H 1R3; firstname.lastname@example.org