Rosario Montirosso1, Livio Provenzi2, Daniela Tavian3, Francesco Morandi4, Andrea Bonanomi5, Sara Missaglia3, Ed Tronick6, Renato Borgatti7. 1. 0-3 Centre for the Study of Social Emotional Development of at Risk Infant, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy. Electronic address: rosario.montirosso@bp.lnf.it. 2. 0-3 Centre for the Study of Social Emotional Development of at Risk Infant, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy. 3. Laboratory of Cellular Biochemistry and Molecular Biology, CRIBENS, Catholic University, Milan, Italy. 4. Pediatric Unit, Sacra Famiglia Hospital, Erba, Como, Italy. 5. Department of Statistics, Catholic University, Milan, Italy. 6. Department of Psychology, University of MA, Boston, USA. 7. Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy.
Abstract
BACKGROUND: Maternal behavior and infant 5-HTTLPR polymorphism have been linked to infants' social stress reactivity and recovery at different ages. Nonetheless, Gene×Environment (G×E) studies focusing on early infancy are rare and have led to mixed results. AIM: To investigate the contribution of maternal social engagement and infants' 5-HTTLPR polymorphism in predicting infants' negative emotionality in response to a social stressor, namely maternal unresponsiveness. STUDY DESIGN: Cross-sectional, G×E study. SUBJECTS: 73 4-month-old infants and their mothers took part to the Face-to-Face Still-Face (FFSF) procedure. OUTCOME MEASURES: A micro-analytical coding of negative emotionality was adopted to measure infants' reactivity to social stress (Still-Face episode) and infants' recovery after social stress (Reunion episode). Maternal contribution was measured as maternal social engagement during the Play episode. Infants were genotyped as S-carriers or L-homozygotes. RESULTS: The interplay between maternal social engagement and infants' genotype was found to be predictive of infants' negative emotionality during both Still-Face and Reunion episodes of the FFSF paradigm. The interaction highlighted that maternal social engagement predicted minor negative emotionality during Still-Face and Reunion episodes for S-carrier infants, but not for L-homozygotes. CONCLUSIONS: Findings extend previous results on adults and children, highlighting that maternal behavior might be a protective factor for stress reactivity and regulation, especially for S-carrier infants who are at risk for heightened stress susceptibility.
BACKGROUND: Maternal behavior and infant 5-HTTLPR polymorphism have been linked to infants' social stress reactivity and recovery at different ages. Nonetheless, Gene×Environment (G×E) studies focusing on early infancy are rare and have led to mixed results. AIM: To investigate the contribution of maternal social engagement and infants' 5-HTTLPR polymorphism in predicting infants' negative emotionality in response to a social stressor, namely maternal unresponsiveness. STUDY DESIGN: Cross-sectional, G×E study. SUBJECTS: 73 4-month-old infants and their mothers took part to the Face-to-Face Still-Face (FFSF) procedure. OUTCOME MEASURES: A micro-analytical coding of negative emotionality was adopted to measure infants' reactivity to social stress (Still-Face episode) and infants' recovery after social stress (Reunion episode). Maternal contribution was measured as maternal social engagement during the Play episode. Infants were genotyped as S-carriers or L-homozygotes. RESULTS: The interplay between maternal social engagement and infants' genotype was found to be predictive of infants' negative emotionality during both Still-Face and Reunion episodes of the FFSF paradigm. The interaction highlighted that maternal social engagement predicted minor negative emotionality during Still-Face and Reunion episodes for S-carrier infants, but not for L-homozygotes. CONCLUSIONS: Findings extend previous results on adults and children, highlighting that maternal behavior might be a protective factor for stress reactivity and regulation, especially for S-carrier infants who are at risk for heightened stress susceptibility.