Opportunities for learning and social interaction in infant sitting: Effects of sitting support,sitting skill,and gross motor delay

The development of independent sitting changes everyday opportunities for learning and has cascading effects on cognitive and language development. Prior to independent sitting, infants experience the sitting position with physical support from caregivers. Why does supported sitting not provide the same input for learning that is experienced in independent sitting? This question is especially relevant for infants with gross motor delay, who require support in sitting for many months after typically developing infants sit independently. We observed infants with typical development (n = 34, ages 4–7 months) and infants with gross motor delay (n = 128, ages 7–16 months) in early stages of sitting development, and their caregivers, in a dyadic play observation. We predicted that infants who required caregiver support for sitting would spend more time facing away from the caregiver and less time contacting objects than infants who could sit independently. We also predicted that caregivers of supported sitters would spend less time contacting objects because their hands would be full supporting their infants. Our first two hypotheses were confirmed; however, caregivers spent surprisingly little time using both hands to provide support, and caregivers of supported sitters spent more time contacting objects than caregivers of independent sitters. Similar patterns were seen in the group of typically developing infants and the infants with motor delay. Our findings suggest that independent sitting and supported sitting provide qualitatively distinct experiences with different implications for social interaction and learning opportunities.

Highlights

• During seated free play, supported sitters spent more time facing away from their caregivers and less time handling objects than independent sitters.
• Caregivers who spent more time supporting infants with both hands spent less time handling objects; however, caregivers mostly supported infants with one or no hands.
• A continuous measure of sitting skill did not uniquely contribute to these behaviors beyond the effect of binary sitting support (supported vs. independent sitter).
• The pattern of results was similar for typically developing infants and infants with gross motor delay, despite differences in age.

     

Intra-couple similarity in dyadic coping and partners’ adjustment to the birth of a child

Unlike individual perceptions of a couple's functioning, couple-level protective factors against poor adjustment to the birth of a child have rarely been studied. This study examined similarity or reciprocal exchanges in dyadic coping (DC) during pregnancy (T1) and at 6 weeks postpartum (T2) and its associations with both partners’ adjustment at 6–9 months postpartum (T3). Ninety-two Portuguese couples provided data on DC, internalizing symptoms, dyadic adjustment and parenting stress. An individual's perceived similarity at T1 positively predicted his or her own internalizing symptoms at T3. One partner's perceived similarity at T2 negatively predicted the other partner's internalizing symptoms and parenting stress at T3. These associations controlled for stereotype effects (i.e., similarity due to shared cultural norms and values). Both partners’ adjustment seems to benefit from unique similarity within the couple after childbirth, while complementarity in DC during pregnancy appears to be more beneficial in the long term. Our findings suggest important refinements to DC-based interventions already aimed to promote similarity in DC.     

Estimating Age-Based Developmental Trajectories Using Latent Change Score Models Based on Measurement Occasion

Abstract

Accelerated longitudinal designs (ALDs) are designs in which participants from different cohorts provide repeated measures covering a fraction of the time range of the study. ALDs allow researchers to study developmental processes spanning long periods within a relatively shorter time framework. The common trajectory is studied by aggregating the information provided by the different cohorts. Latent change score (LCS) models provide a powerful analytical framework to analyze data from ALDs. With developmental data, LCS models can be specified using measurement occasion as the time metric. This provides a number of benefits, but has an important limitation: It makes it not possible to characterize the longitudinal changes as a function of a developmental process such as age or biological maturation. To overcome this limitation, we propose an extension of an occasion-based LCS model that includes age differences at the first measurement occasion. We conducted a Monte Carlo study and compared the results of including different transformations of the age variable. Our results indicate that some of the proposed transformations resulted in accurate expectations for the studied process across all the ages in the study, and excellent model fit. We discuss these results and provide the R code for our analysis.