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Effects of an attachment-based intervention on daily cortisol moderated by dopamine receptor D4: A randomized control trial on 1- to 3-year-olds screened for externalizing behavior

Published online by Cambridge University Press:  07 July 2008

Marian J. Bakermans-Kranenburg ,
Marinus H. Van IJzendoorn ,
Judi Mesman ,
Lenneke R. A. Alink  and
Femmie Juffer
Marian J. Bakermans-Kranenburg*
Affiliation:
Leiden University
Marinus H. Van IJzendoorn*
Affiliation:
Leiden University
Judi Mesman
Affiliation:
Leiden University
Lenneke R. A. Alink
Affiliation:
Leiden University
Femmie Juffer
Affiliation:
Leiden University
*
Address correspondence and reprint requests to: Marian Bakermans-Kranenburg or Marinus van IJzendoorn, Centre for Child and Family Studies, Leiden University, P.O. Box 9555, Leiden NL-2300 RB, The Netherlands; E-mail: bakermans@fsw.leidenuniv.nl or vanijzen@fsw.leidenuniv.nl.
Address correspondence and reprint requests to: Marian Bakermans-Kranenburg or Marinus van IJzendoorn, Centre for Child and Family Studies, Leiden University, P.O. Box 9555, Leiden NL-2300 RB, The Netherlands; E-mail: bakermans@fsw.leidenuniv.nl or vanijzen@fsw.leidenuniv.nl.
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Abstract

The effect of the Video-Feedback Intervention to Promote Positive Parenting and Sensitive Discipline (VIPP-SD) on daily cortisol production was tested in a randomized controlled trial with 130 families with 1- to 3-year-old children screened for their relatively high levels of externalizing behavior. Six 1.5-hr intervention sessions focusing on maternal sensitivity and discipline were conducted with individual families at their homes. Children in the intervention group showed lower cortisol levels, with a moderating role of the dopamine receptor D4 (DRD4) VNTR exon III polymorphism. The VIPP-SD program proved to be effective in decreasing daily cortisol production in children with the DRD4 7-repeat allele, but not in children without the DRD4 7-repeat allele. Our findings indicate that children are differentially susceptible to intervention effects dependent on the presence of the 7-repeat DRD4 allele.

Type
Research Article
Information
Development and Psychopathology , Volume 20 , Issue 3 , Summer 2008 , pp. 805 - 820
Copyright
Copyright © Cambridge University Press 2008

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Footnotes

This study is part of the research project on Screening and Intervention of Problem Behavior in Toddlerhood (SCRIPT). The study is supported by Grant 2200.0097 from The Netherlands Organization for Health Research and Development (ZonMw) to Marinus van IJzendoorn and Femmie Juffer. Support from The Netherlands Organization for Scientific Research NWO (Rubicon to Lenneke Alink, VENI to Judi Mesman, VIDI to Marian Bakermans-Kranenburg, and SPINOZA Prize to Marinus van IJzendoorn) is gratefully acknowledged. We thank Mirjam Stolk, Jantien van Zeijl, Femke Pijlman, and Hans Koot for their contributions to the various parts of the intervention study and Base-Clear for the genotyping. Last, but not least, we thank the parents and children who participated in our study, as well as the students who assisted in various phases of the SCRIPT project. The contributions of the first and the second author to this paper are equal.

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