Growth of Expressive Syntax in Children With Fragile X Syndrome

Purpose This research explored syntactic growth in children with fragile X syndrome (FXS) over a 5-year period, and variability in growth in relation to autism symptoms, nonverbal cognition, maternal responsivity, and gender. Method Language samples at 4 time points from 39 children with FXS, 31 boys and 8 girls, were analyzed using the Index of Productive Syntax (Scarborough, 1990) and mean length of utterance (Brown, 1973). The degree of autism symptoms was evaluated using the Childhood Autism Rating Scale (Schopler, Reichler, & Renner, 1988) at the first time point. Maternal responsivity estimates were averaged across time points. Results Children with FXS showed significant syntactic growth over time and a significant plateau (quadratic trend) in the later observations. Children who exhibited more autism symptoms at Time 1 had significantly lower syntactic abilities over time than children who exhibited fewer autism symptoms. Nonverbal cognition significantly predicted mean length of utterance scores but not Index of Productive Syntax scores. Maternal responsivity was not a significant predictor of syntactic outcomes. Girls with FXS generally demonstrated better expressive syntax than boys with FXS with notable individual differences. Conclusion Despite significant growth over time, expressive syntax is a vulnerable domain for children with FXS, especially for those with severe autism symptoms. Clinical implications arising from the current findings are discussed.

Physiological Correlates of Maternal Responsivity in Mothers of Preschoolers With Fragile X Syndrome

The present study examined the relationship between salivary cortisol and maternal responsiveness in mothers of boys with fragile X syndrome (FXS). Maternal responsivity is strongly associated with child outcomes, and children with FXS are at risk for compromised development due to intellectual disability and problem behavior. Increased understanding of the nature and underlying mechanisms of maternal responsivity in FXS is important to optimize outcomes in children with FXS and contribute to improved family cohesion. Data from 36 mother-child dyads indicated a complex age effect with elevated cortisol levels associated with high maternal responsivity scores when children are young and low responsivity scores when children are older. Implications of these findings and directions for future research are discussed.

Effect of Sustained Maternal Responsivity on Later Vocabulary Development in Children With Fragile X Syndrome

Purpose This research explored whether sustained maternal responsivity (a parent–child interaction style characterized by warmth, nurturance, and stability as well as specific behaviors, such as contingent positive responses to child initiations) was a significant variable predicting vocabulary development of children with fragile X syndrome through age 9 years. Method Fifty-five mother–child dyads were followed longitudinally when children were between 2 and 10 years of age. Measures of maternal responsivity and child vocabulary were obtained at regular intervals starting at age 2.9 years. Sustained responsivity was indicated by the average responsivity measured over Observations 2–5. Responsivity at the 1st time period, autism symptoms, and cognitive development were used as control variables. Results After controlling for development and autism symptoms, the authors found significant effects for sustained responsivity on receptive vocabulary, expressive vocabulary, and the rate of different words children produced through age 9. Conclusions Maternal responsivity, which is typically a variable of interest during early childhood, continues to be a significant variable, predicting vocabulary development through the middle childhood period. Thus, responsivity is a potential target for language interventions through this age period.

Influences on Maternal Responsivity in Mothers of Children With Fragile X Syndrome

This study investigated the influence of maternal and child variables on the maternal responsivity of 55 mothers with young children with fragile X syndrome. Data included video observations of mother-child interactions in four different contexts, standardized assessments with the children, and standardized questionnaires for the mothers. The video observations were coded for child communication acts; maternal responsivity was coded at two levels: a more general measure and a behavior-by-behavior measure. Results indicated that child developmental level and language ability strongly influenced behavior-by-behavior responsivity, while maternal IQ was the strongest predictor of both general and behavior-by-behavior responsivity, after controlling for child developmental level.

Maternal Responsivity Predicts Language Development in Young Children With Fragile X Syndrome

The relationship between early maternal responsivity and later child communication outcomes in young children with fragile X syndrome was investigated. Data were obtained from 55 mother–child dyads over a 36-month period. Performance data were obtained at each measurement point from video observations of four different contexts. These were coded for (a) child communication behaviors, (b) parent responsivity, and (c) behavior management behaviors. Results indicate that early maternal responsivity predicts the level of four important child language outcomes at 36 months of age after controlling for child developmental level and autism symptomology.