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

Responsive Parenting as a Target for Telehealth Language Interventions in Fragile X Syndrome: Implications for Scalability and Best Practices

This review highlights the ways in which telehealth procedures can be implemented to help bridge the research-to-practice gap in supporting developmental outcomes for youth with fragile X syndrome (FXS). We review how the literature to date has informed potential treatment targets in the areas of speech and language development with a focus on understanding and supporting the dyadic relationship between the child and their biological mother, who is also impacted biologically. Notably, parental responsivity is an area that is strongly related to child language outcomes, both early and into adolescence, and thus, it is an important treatment target for subsequent interventions. To date, several parent-implemented interventions have been done in FXS across a broad age range (2-17-year-olds) all showing support not only that parents are successful in learning responsive strategies but also that there are subsequent impacts to child language development. Moreover, these interventions were successfully implemented at a distance through telehealth procedures including video teleconferencing and shared recordings of parent-child interactions. This review also addresses potential moderators of treatment gains. Implications for scaling such interventions in the future as well as best practices for incorporating telehealth procedures into future research and intervention programs are also discussed.

A biopsychosocial perspective on maternal parenting in the first two years of infant life

Guided by a biopsychosocial perspective of mothering, this study investigated the interplay among biological (maternal cortisol reactivity), psychological (maternal depressive symptoms), and social (infant emotion and regulation) factors in contributing to early changes in maternal parenting. Participants were 1292 low-income, mother-infant pairs, assessed when the infants were 6-months (T1), 15-months (T2), and 24-months old (T3). Maternal parenting was observed at all assessment points. At T1, infant emotion expression and orienting towards mothers were observed, when maternal cortisol reactivity was assessed. Mothers reported their depressive symptoms at T1. Exploratory factor analysis revealed two parenting factors across time points: positive engagement and negative intrusiveness. Second-order latent growth curve models revealed interactions among maternal cortisol reactivity, depressive symptoms, and child negative emotion/orienting at T1 in predicting intercepts and slopes of two parenting factors. T1 maternal cortisol reactivity was associated with a higher positive engagement intercept for infants having high negative emotion at T1, but a lower positive engagement intercept for infants with low negative emotion at T1, under low T1 maternal depressive symptoms. T1 maternal cortisol reactivity was also related to a lower negative intrusiveness intercept for infants showing high orienting at T1. Longitudinally, maternal cortisol reactivity at T1 predicted a faster decline in positive engagement when infants showed high negative emotion at T1, but a slower decline when infants were less negative at T1. This study reveals a bivalent adaptation process in maternal sensitivity and enhances the current understanding of how biopsychosocial factors contribute to maternal parenting in low-income families.

Maternal Mental Health and Parenting Stress and Their Relationships to Characteristics of the Child With Fragile X Syndrome

Although previous research supports the notion that characteristics of both the child and the mother impact maternal well-being and parenting stress in mothers of children with FXS, more work is needed in which self-report measures are supplemented by physiological measures of stress and well-being. The inclusion of physiological measures, such as heart rate variability (HRV), may provide a window into the biological origins and consequences of maternal perceptions of their experiences, including the challenges of raising a child with developmental challenges. The proposed project, therefore, involved the collection of multimodal assessment data from mothers and their school-aged children with FXS. Further, given the importance of understanding how mothers of youth with FXS are faring in their everyday environment, the present study collected all data using telehealth procedures and wearable technology. Participants were 20 biological mothers and their children with FXS between the ages of 6 and 11 years. We measured maternal mental health and parenting stress through self-report as well as through HRV as a more objective measure of psychological well-being. We also examined the associations between these variables and child characteristics such as externalizing and internalizing behaviors as well as autism symptomatology. We found significant support for an elevated rate of depressive symptoms in the sample of mothers (35%) and some potential indicators for heightened rates of anxiety (15%) when compared to normed samples and rates in the general population. We also found that the mothers presented with an atypical HRV profile akin to those experiencing depression or chronic stress, although limitations of the present measure suggest the need for additional confirmatory research. Further, we found that child externalizing behaviors were the primary correlates of maternal well-being. These findings contribute to the growing body of literature regarding the unique challenges faced by these mother-child dyads and supports the importance of increasing the availability of services available to these mothers, not only for meeting the needs of their children's development and behavior, but in supporting their own well-being as well.

Of Men and Mice: Modeling the Fragile X Syndrome

The Fragile X Syndrome (FXS) is one of the most common forms of inherited intellectual disability in all human societies. Caused by the transcriptional silencing of a single gene, the fragile x mental retardation gene FMR1, FXS is characterized by a variety of symptoms, which range from mental disabilities to autism and epilepsy. More than 20 years ago, a first animal model was described, the Fmr1 knock-out mouse. Several other models have been developed since then, including conditional knock-out mice, knock-out rats, a zebrafish and a drosophila model. Using these model systems, various targets for potential pharmaceutical treatments have been identified and many treatments have been shown to be efficient in preclinical studies. However, all attempts to turn these findings into a therapy for patients have failed thus far. In this review, I will discuss underlying difficulties and address potential alternatives for our future research.

Reduced vagal tone in women with the FMR1 premutation is associated with FMR1 mRNA but not depression or anxiety

Background

Autonomic dysfunction is implicated in a range of psychological conditions, including depression and anxiety. The fragile X mental retardation-1 (FMR1) premutation is a common genetic mutation that affects ~1:150 women and is associated with psychological vulnerability. This study examined cardiac indicators of autonomic function among women with the FMR1 premutation and control women as potential biomarkers for psychological risk that may be linked to FMR1.

Methods

Baseline inter-beat interval and respiratory sinus arrhythmia (a measure of parasympathetic vagal tone) were measured in 35 women with the FMR1 premutation and 28 controls. The women completed anxiety and depression questionnaires. FMR1 genetic indices (i.e., CGG repeat, quantitative FMRP, FMR1 mRNA, activation ratio) were obtained for the premutation group.

Results

Respiratory sinus arrhythmia was reduced in the FMR1 premutation group relative to controls. While depression symptoms were associated with reduced respiratory sinus arrhythmia among control women, these variables were unrelated in the FMR1 premutation. Elevated FMR1 mRNA was associated with higher respiratory sinus arrhythmia.

Conclusions

Women with the FMR1 premutation demonstrated autonomic dysregulation characterized by reduced vagal tone. Unlike patterns observed in the general population and in study controls, vagal activity and depression symptoms were decoupled in women with the FMR1 premutation, suggesting independence between autonomic regulation and psychopathological symptoms that is atypical and potentially specific to the FMR1 premutation. The association between vagal tone and mRNA suggests that molecular variation associated with FMR1 plays a role in autonomic regulation.

Pragmatic Language Features of Mothers With the FMR1 Premutation Are Associated With the Language Outcomes of Adolescents and Young Adults With Fragile X Syndrome

PURPOSE

Pragmatic language difficulties have been documented as part of the FMR1 premutation phenotype, yet the interplay between these features in mothers and the language outcomes of their children with fragile X syndrome is unknown. This study aimed to determine whether pragmatic language difficulties in mothers with the FMR1 premutation are related to the language development of their children.

METHOD

Twenty-seven mothers with the FMR1 premutation and their adolescent/young adult sons with fragile X syndrome participated. Maternal pragmatic language violations were rated from conversational samples using the Pragmatic Rating Scale (Landa et al., 1992). Children completed standardized assessments of vocabulary, syntax, and reading.

RESULTS

Maternal pragmatic language difficulties were significantly associated with poorer child receptive vocabulary and expressive syntax skills, with medium effect sizes.

CONCLUSIONS

This work contributes to knowledge of the FMR1 premutation phenotype and its consequences at the family level, with the goal of identifying modifiable aspects of the child's language-learning environment that may promote the selection of treatments targeting the specific needs of families affected by fragile X. Findings contribute to our understanding of the multifaceted environment in which children with fragile X syndrome learn language and highlight the importance of family-centered intervention practices for this group.