Paternal involvement and early infant neurodevelopment: the mediation role of maternal parenting stress.

BACKGROUND: Father-child interactions are associated with improved developmental outcomes among infants. However, to the best of our knowledge, no study has addressed the effects of paternal involvement on the neurodevelopment of infants who are less than 6 months of age, and no study has reported how maternal parenting stress mediates the relationship between paternal involvement and infant neurodevelopment during early infancy. This study investigates the direct and indirect relationship between paternal involvement and infant neurodevelopment at 3-4 months of age. The indirect relationship was assessed through the mediating factor of maternal parenting stress. METHODS: The participants were recruited through the Sesalmaul Research Center's website from April to June 2014. The final data included 255 mothers and their healthy infants, who were aged 3-4 months. The mothers reported paternal involvement and maternal parenting stress by using Korean Parenting Alliance Inventory (K-PAI) and Parenting Stress Index (PSI), respectively. Experts visited the participants' homes to observe infant neurodevelopment, and completed a developmental examination using Korean version of the Ages and Stages Questionnaire II (K-ASQ II). A hierarchical multiple regression analysis was used for data analysis. RESULTS: Infants' mean ages were 106 days and girls accounted for 46.3%. The mean total scores (reference range) of the K-PAI, PSI, and the K-ASQ II were 55.5 (17-68), 45.8 (25-100), and 243.2 (0-300), respectively. Paternal involvement had a positive relationship with K-ASQ II scores (ß = 0.29, p < 0.001) at 3-4 months of age, whereas maternal parenting stress was negatively related with K-ASQ II scores (ß = -0.32, p < 0.001). Maternal parenting stress mediated the relationship between paternal involvement and early infant neurodevelopment (Z = 3.24, p < 0.001). A hierarchical multiple regression analysis showed that paternal involvement reduced maternal parenting stress (ß = -0.25, p < 0.001), which led to positive infant outcomes (ß = 0.23, p < 0.001). CONCLUSIONS: Paternal involvement is significantly associated with infant neurodevelopment during early infancy, and maternal parenting stress partially mediates that association. This result emphasizes the importance of fathers' involvement and mothers' parenting stress on early infant neurodevelopment.

Serial diffusion tensor images during infancy and their relationship to neuromotor outcomes in preterm infants.

BACKGROUND: Even preterm infants with normal magnetic resonance imaging (MRI) results are at greater risk for neuromotor dysfunction. OBJECTIVES: Our aim was to compare serial diffusion tensor imaging (DTI) data from preterm infants without apparent brain abnormalities on magnetic resonance imaging with those from term controls and to investigate the white matter (WM) region associated with neuromotor outcomes. METHODS: We obtained serial DTIs from 21 preterm infants at term-equivalent age (TEA) and 1 year of corrected age. As controls, 15 term neonates and 20 newly recruited term infants aged 1 year underwent DTI. Preterm and term infants at 1 year of age were assessed with the Bayley Scales of Infant Development, second edition. Tract-based spatial statistics and regions of interest were used for analysis. RESULTS: At TEA, the entire WM development was delayed in the preterm infants compared with the term controls, but at 1 year of age, the WM development, except for that of the corpus callosum (CC), had reached the development level of the term controls. The psychomotor developmental index was positively correlated with the fractional anisotropy (FA) in the CC (particularly in the body and splenium) at 1 year of age after correcting for gestational age, chronic lung disease, and postnatal infection. CONCLUSIONS: The CC of the preterm infants was consistently underdeveloped compared with that of the term controls. The FA in the CC, particularly in the body and splenium at 1 year of age, well reflected the degree of motor function in infants without apparent brain abnormalities.