In BabyTwins, we are investigating the contribution of genetic and environmental factors to individual differences in a variety of traits in infancy.


The generous parental benefits in Sweden create unique possibilities for studying infant twins. We are using the classic twin design (comparing within pair similarities of monozygotic (MZ) - dizygotic (DZ) twins) and the MZ differences design to understand the role of genetics and shared and non-shared environments on infant brain and behavioral traits. The twins are being assessed at five months of age using brain based techniques (electroencephalography; EEG) and a range of behavioral methods (in-person assessments including eye tracking, behavioral experiments, parent–child interaction observation, and parental questionnaires covering temperament, sleep habits, adaptive functioning, and language development). Saliva is taken for molecular genetic analyses. To maximize synergies, the protocol is largely overlapping with the 5-month-old protocol used in the longitudinal study of infants at risk for autism and ADHD.


The study is funded by EU (H2020 MSC European Training Network ‘BRAINVIEW’, 2015-2017, co-PIs = Terje Falck-Ytter, Sven Bölte) and from Stiftelsen Riksbankens Jubilemusfond (RJ; 2016-2020, PI = Terje Falck-Ytter).


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Terje Falck-Ytter

Principal Researcher
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