Taking parent personality and child temperament into account in child language development

Disentangling genetic and environmental influences on early language development: The interplay of genetic propensity for negative emotionality and surgency, and parenting behavior effects on early language skills in an adoption study

Parenting and children's temperament are important influences on language development. However, temperament may reflect prior parenting, and parenting effects may reflect genes common to parents and children. In 561 U.S. adoptees (57% male) and their birth and rearing parents (70% and 92% White, 13% and 4% African American, and 7% and 2% Latinx, respectively), this study demonstrated how genetic propensity for temperament affects language development, and how this relates to parenting. Genetic propensity for negative emotionality inversely predicted language at 27 months (β = -.15) and evoked greater maternal warmth (β = .12), whereas propensity for surgency positively predicted language at 4.5 years (β = .20), especially when warmth was low. Parental warmth (β = .15) and sensitivity (β = .19) further contributed to language development, controlling for common gene effects.

Toddler negative affectivity and effortful control: Relations with parent-toddler conversation engagement and indirect effects on language

Evidence that early parent-child conversation supports early language development suggests a need to understand factors that account for individual differences in parent-child conversation engagement. Whereas most studies focus on demographic factors, we investigated the role of toddler temperament in a longitudinal study of 120 economically strained families. Specifically, we investigated the degree to which toddlers' negative affectivity and effortful control, considered together as a composite reflecting challenging temperament, accounted for variability in parent-toddler conversation engagement, and whether the frequency of that engagement mediated associations between toddler temperament and toddler expressive language skills. Toddler challenging temperament (i.e., high negative affectivity and low effortful control) and parent-toddler conversation engagement were measured at 18 and 30 months. Toddler expressive language skills were measured at 18, 24, and 36 months. As expected, a path model indicated inverse relations between toddler challenging temperament and concurrent parent-toddler conversation engagement at both 18 and 30 months. Unexpectedly, there were no direct associations between toddler challenging temperament and toddler expressive language skills either concurrently or longitudinally. However, we found indirect effects of toddler challenging temperament on later toddler expressive language skills via parent-toddler conversation engagement. Findings highlight the importance of considering toddler temperamental characteristics in addition to family demographics as important factors that account for variability in parent-toddler conversation engagement.

Temperament and children's accuracy and attention during word learning

When hearing a novel word, children typically rule out familiar objects and assume a speaker is referring to a novel object. This strategy is known as fast mapping, and young children use this with a high degree of accuracy. However, not all children engage in fast mapping to the same extent and temperament can play a role. Shyness is associated with poorer fast mapping and less attention to target objects, which is associated with poorer retention (Hilton et al., 2019; Hilton & Westermann, 2017). We further investigated the relationship between temperament and fast mapping by presenting 2.5-year-old children with 8 familiar target fast mapping trials and 4 novel target trials presented twice. We considered two temperamental dimensions: approachability due to its similarity to shyness; and reactivity, which could predict children's capacity to engage during fast mapping. We found an association between approachability and fast mapping accuracy the second time children fast-mapped novel targets, and approachability was associated with greater retention accuracy. Reactivity predicted proportions of target looking during fast mapping with less reactive temperament scores associated with greater focus on targets. This provides support for a relationship between two dimensions of temperament and fast mapping and retention. Approachability may be associated with a further opportunity to fast map and memory for novel words, and/or how willing children are to guess the targets. Reactivity may be associated with the capacity to focus during word learning situations. Different aspects of temperament could have implications for children's capacity to disambiguate and learn words.

Early temperament as a predictor of language skills at 40 months

Background

Mastering language involves the development of expressive and receptive skills among children. While it has been speculated that early temperament plays a role in the acquisition of language, the actual mechanism has not yet been explored. We investigated whether temperament at 18 months predicted expressive or receptive language skills at 40 months.

Methods

A representative sample of 901 children and their mothers who were enrolled and followed-up longitudinally in the Hamamatsu Birth Cohort for Mothers and Children study was included in the analysis. Child temperament was measured at 18 months using the Japanese version of the Early Childhood Behavior Questionnaire. Expressive and receptive language skills were measured at 40 months using the Mullen Scales of Early Learning.

Results

The multiple regression analysis, adjusting for potential confounders, suggested that higher motor activation (fidgeting) at 18 months was associated with lower expressive and receptive language skills at 40 months. Higher perceptual sensitivity was associated with higher expressive and receptive language skills at 40 months.

Conclusions

Specific temperament at 18 months of age predicted the development of the child’s expressive and receptive language skills at 40 months.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03116-5.