Location: Children's Nutrition Research CenterTitle: Association of prenatal maternal perceived stress with a sexually dimorphic measure of cognition in 4.5-month-old infants
|MERCED-NIEVES, FRANCHESKA - University Of Illinois|
|AGUIAR, ANDREA - University Of Illinois|
|DZWILESKI, KELSEY - University Of Illinois|
|MUSAAD, SALMA - Children'S Nutrition Research Center (CNRC)|
|KORRICK, SUSAN - Brigham & Women'S Hospital|
|SCHANTZ, SUSAN - University Of Illinois|
Submitted to: Neurotoxicology and Teratology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/4/2019
Publication Date: 1/1/2020
Citation: Merced-Nieves, F.M., Aguiar, A., Dzwileski, K.L., Musaad, S., Korrick, S.A., Schantz, S.L. 2020. Association of prenatal maternal perceived stress with a sexually dimorphic measure of cognition in 4.5-month-old infants. Neurotoxicology and Teratology. 77:106850. https://doi.org/10.1016/j.ntt.2019.106850.
Interpretive Summary: Children of mothers who experience stress during pregnancy are at increased risk for low birth weight as well as issues related to thinking skills such as attention, problem solving and creativity. Studies show that these risks could differ by child gender. Thus, increasing our understanding of the effects of stress during pregnancy on child brain development can help us decide when a child is at risk and needs medical evaluation. We studied the relationship between mothers' stress during pregnancy and 4.5 months old infants' looking behaviors using infrared eye tracking. Looking behaviors are used to examine physical reasoning of the infant and are affected by visual development. Infants tend to look longer at events that are new or unexpected. For example, if a toy is expected to remain in place but we move it, infants tend to look at it longer because they are surprised to see it move. Normally, girls look at the unexpected event longer than boys. In this study, we found that when mothers were highly stressed during pregnancy, the girls' looking time was shortened, but not the boys'. The results provide evidence that maternal stress during pregnancy can affect infant brain development and that girls are more sensitive to this effect than boys.
Technical Abstract: Maternal prenatal stress can adversely impact subsequent child neurodevelopment, but little is known about its effect on cognitive development in infancy. This analysis of 107 infants from a prospective birth cohort assessed whether prenatal stress disrupts sexually dimorphic performance typically observed on a physical reasoning task. Maternal stress was assessed at 8–14 and 33–37 gestational weeks using the Perceived Stress Scale. Stress was defined as: low (scores below the median at both times), medium (scores above the median at one of the two times), and high (scores above the median at both times). At 4.5 months infants saw videos of two events: one impossible and the other possible. In the impossible event a box was placed against a wall without support underneath. In the possible event the box was placed against the wall, supported by the floor. Looking time at each event was recorded via infrared eye-tracking. Previous literature has shown that, at 4.5 months of age, girls typically look significantly longer at the impossible than at the possible event, suggesting that they expect the unsupported box to fall and are surprised when it does not. Boys tend to look equally at the two events suggesting that they do not share this expectation. This sex difference was replicated in the current study. General linear models stratified by sex and adjusted for household income, maternal education, mother's age at birth, infant's age at exam, and order of event presentation revealed that girls whose mothers reported high perceived stress during pregnancy had shorter looking time differences between the impossible and possible events than girls whose mothers reported low perceived stress (Beta=-7.1; 95% CI: -12.0, -2.2 s; p=0.006). Similar to boys, girls in the highest stress category spent about the same amount of time looking at each event. For boys, there were no significant looking time differences by maternal stress level. This finding suggests prenatal stress is associated with a delay in the development of physical reasoning in girls.