Skip to main content
eScholarship
Open Access Publications from the University of California

Scholarly Works (112 results)

  • Article
  • Peer Reviewed
UC Davis Previously Published Works (2019)
This study was designed to establish the extent of delay in complex sentence use by females with fragile X syndrome (FXS) and to identify sources of variability among individuals. Females with FXS (n = 16; 10;2-15;7) and younger typically developing girls (n = 17; 4;1-8;11) were group-wise matched on nonverbal cognition and receptive syntax. Language samples (conversation and narration) yielded syntactic complexity in terms of mean length of C-unit (MLCU) and Developmental Level sentence coding (DLevel; Rosenberg & Abbeduto, 1987 ). Complex syntax was not weaker than developmental expectations; however, MLCU was lower than expected for age. Phonological memory and verbal working memory correlated with measures of syntactic complexity in narration. Discourse demands may play an important role in the language produced by females with FXS.
    Cover page: Syntactic Ability of Girls With Fragile X Syndrome: Phonological Memory and Discourse Demands on Complex Sentence Use
    • Article
    • Peer Reviewed
    UC Davis Previously Published Works (2023)
    Lack of diversity in IDD research is typically conceptualized only in terms of (1) recruitment of samples that do not appropriately represent the sociodemographics of the population, or (2) the limited number of researchers from historically marginalized backgrounds. Critically, the field also suffers from over-reliance on perspectives and social systems of dominant culture-both in how disability is regarded and in relation to other dimensions of identity and culture. These lenses lead to research findings that reinforce, rather than reduce, social inequities. We propose a framework that minimizes reliance on diagnostic categories, shifts from deficit- to person-centered models, acknowledges people's multiple identities, and includes self-advocates and diverse communities as partners in the research enterprise. The systems change necessary to support this framework is described.
      Cover page: Toward Equity in Research on Intellectual and Developmental Disabilities.
      • Article
      • Peer Reviewed
      UC Davis Previously Published Works (2023)
      In "Toward Equity in Research on Intellectual and Developmental Disabilities," we sought to make entrenched assumptions and practices of intellectual and developmental disabilities research visible by explicitly describing the status quo in terms of models of disability, participant and researcher identities, research priorities, and biases in measurement and treatment approaches. We then curated individual- and systems-level actions drawn from disability justice and broader social justice lenses to offer a way forward. We focused on three major areas (i.e., intersectionality and person-centered approaches, participatory research, and interprofessional collaboration), depicting influences, methods, and actions in a framework of disability, identity, and culture. In this Author Response, we address five commentaries that critique and extend that synthesis.
        Cover page: The Work Ahead for Intellectual and Developmental Disabilities Research.
        • Article
        • Peer Reviewed
        UC Davis Previously Published Works (2014)
        Autism spectrum disorder (ASD) is a common comorbid condition in people with fragile X syndrome (FXS). It has been assumed that ASD symptoms reflect the same underlying psychological and neurobiological impairments in both FXS and non-syndromic ASD, which has led to the claim that targeted pharmaceutical treatments that are efficacious for core symptoms of FXS are likely to be beneficial for non-syndromic ASD as well. In contrast, we present evidence from a variety of sources suggesting that there are important differences in ASD symptoms, behavioral and psychiatric correlates, and developmental trajectories between individuals with comorbid FXS and ASD and those with non-syndromic ASD. We also present evidence suggesting that social impairments may not distinguish individuals with FXS with and without ASD. Finally, we present data that demonstrate that the neurobiological substrates of the behavioral impairments, including those reflecting core ASD symptoms, are different in FXS and non-syndromic ASD. Together, these data suggest that there are clinically important differences between FXS and non-syndromic ASD that are masked by reliance on the categorical diagnosis of ASD. We argue for use of a symptom-based approach in future research, including studies designed to evaluate treatment efficacy.
          Cover page: The fragile X syndrome–autism comorbidity: what do we really know?
          • Article
          • Peer Reviewed
          UC Davis Previously Published Works (2022)
          Broader phenotypes associated with genetic liability, including mild difficulties with pragmatic language skills, have been documented in mothers of children with autism spectrum disorder (ASD) and mothers of children with fragile X syndrome (FXS). This study investigated the relationship between pragmatic difficulties and indicators of maternal well-being and family functioning. Pragmatic difficulty was associated with loneliness in mothers of children with ASD or FXS, and with depression, decreased life satisfaction, and poorer family relationship quality in mothers of children with FXS only. Results inform subtle maternal pragmatic language difficulties as a risk factor that that may contribute to reduced health and well-being, informing tailored support services to better meet the unique needs of families of children with ASD or FXS.
            • Article
            • Peer Reviewed
            UC Davis Previously Published Works (2017)
            We examined inferential language use by youth with Down syndrome (DS) in the context of narrative storytelling relative to younger typically developing (TD) children and same-aged peers with fragile X syndrome (FXS) matched on nonverbal cognitive ability level. Participants' narratives were coded for the use of different types of inferential language. Participants with DS used proportionately less inferential language overall relative to their counterparts with TD or FXS, although mean length of utterance accounted for group differences observed for the DS-TD group comparison only. Patterns of inferential language use varied across inferential subtypes and across participant groups, with mean length of utterance playing a significant role in group differences. These findings suggest potential syndrome specificity to the DS phenotype regarding impairments in inferential language use that can be partially explained by level of expressive syntactic ability and should be considered in future research. Clinical interventions within the DS population, therefore, should target to some extent the use of inferential language and complex sentence structure.
              Cover page: Inferential language use by youth with Down syndrome during narration
              • Article
              • Peer Reviewed
              UC Davis Previously Published Works (2017)
              In addition to significant cognitive delays, boys with fragile X syndrome display phenotypic characteristics that include delays in language, inattention, social anxiety, and escape-maintained challenging behaviors. Despite these challenges, families affected by fragile X syndrome often have limited access to center-based intervention programs. The present study utilized a multiple baseline design across participants to examine the preliminary effectiveness of a 12-week, parent-implemented spoken language intervention for three 5- to 7-year-old boys with fragile X syndrome. The goal of the intervention was to teach the biological mothers of each boy to use a set of verbally responsive language support strategies while participating in shared book reading activities with her child. All aspects of the intervention, including pre- and post-treatment measures, were delivered into the family's home via distance video teleconferencing. Results from this study provide preliminary support for the efficacy of this parent-implemented language intervention approach by demonstrating generalized improvements in both targeted maternal strategy use and measures of child spoken language. The present study expands upon prior language intervention research utilizing distance delivery of services for families affected by fragile X syndrome. Additionally, the study provides early support for the feasibility of collecting pre- and post-treatment assessments at a distance.
                Cover page: Distance delivery of a parent-implemented language intervention for young boys with fragile X syndrome
                • Article
                • Peer Reviewed
                UC Davis Previously Published Works (2014)
                This study aimed to characterize social cognition, executive functions (EFs), and everyday social functioning in adolescent girls with fragile X syndrome, and identify relationships among these variables. Participants were 20 girls with FXS and 20 age-matched typically developing peers. Results showed significant between-groups differences in social cognition, accounted for by differences in IQ and language. Within the FXS group, IQ and language were related to social cognition; parent-reported social functioning was related to language and EFs; and self-reported social functioning was generally good and not related to cognitive or social cognition variables. Results suggest that intervention might focus on managing language and cognitive contributions to social functioning, rather than social cognition, and underscore the importance of considering parent and adolescent perspectives.
                  Cover page: Social Cognition in Adolescent Girls With Fragile X Syndrome
                  • Thesis
                  • Peer Reviewed
                  UC Davis Electronic Theses and Dissertations (2021)

                  Children with fragile X syndrome (FXS) have significant delays in many domains of functioning. Biological mothers of children with FXS are at an increased genetic risk for experiencing cognitive, physical, and mental health challenges. Parental mental health challenges and stress are often associated with reduced marital cohesion and satisfaction, which is likely to spill over and negatively affect the parent-child relationship for both mothers and fathers. Past research shows that parentally responsive behavior positively influences language development in both neurotypical children and children with intellectual and developmental disabilities, including those with FXS. However, the majority of past studies on parent-child interactions, and families of children with FXS more generally, have focused exclusively on the mother-child relationship. Therefore, very little is known about fathers in these families, including their well-being and their role in the child’s development. The current dissertation fills this gap by examining multiple features of the family environment, including the mother-father relationship, the mother-child relationship, and the father-child relationship in 23 families of children with FXS. Study 1 examined parental and couple well-being and associations between child functioning and these domains. Mothers and fathers independently completed questionnaires regarding their mental health, parenting stress, couples satisfaction, and dyadic coping in their relationship. Parents also independently completed questionnaires regarding their child’s challenging behaviors and symptoms of autism spectrum disorder (ASD). One parent also completed an interview about the child’s adaptive functioning. Results from this study indicated that mothers and fathers in these families experienced elevated levels of clinically significant mental health challenges and parenting stress compared to levels reported in the general population. However, despite these challenges, the majority of both mothers and fathers reported average to above average levels of couple well-being (i.e., couples satisfaction and dyadic coping). Multilevel models indicated that higher levels of parenting stress predicted lower levels of both couples satisfaction and dyadic coping. Additionally, multilevel models indicated that higher levels of child challenging behavior predicted higher levels of mental health challenges and parenting stress as well as lower levels of couples satisfaction and dyadic coping. Moreover, the parents of children with higher levels of adaptive functioning reported lower levels of parenting stress and higher levels of couples satisfaction. There were no significant differences in these relationships between mothers and fathers. Study 2 examined relationships among maternal responsivity, paternal responsivity, and parental and couple functioning. Mothers and fathers separately engaged in 12-minute dyadic play-based interactions with their child. These interactions were recorded via secure teleconferencing in the families’ homes. Recordings were transcribed and coded for the presence of parentally responsive behaviors and behavior management strategies. Results indicated significant correspondences between mothers’ and fathers’ frequencies and rates of responsive behaviors during the parent-child dyadic interactions. However, overall, mothers used comments more frequently than fathers, and fathers used a higher proportion of behavior management utterances compared to mothers. Multilevel models indicated that higher levels of parenting stress predicted lower rates of parental responsivity and higher rates of behavior management, but these effects were only marginally significant. Couples satisfaction did not predict either category of parent behavior. Study 3 examined relationships among maternal responsivity, paternal responsivity, and child language; it also examined relationships between child characteristics (i.e., challenging behavior, ASD symptoms, and adaptive behavior) and child language as well as parent behavior. Measures of parent and child language were obtained from the transcripts of the mother-child and father-child interactions. The measures were talkativeness, lexical diversity, and syntactic complexity. Multilevel models indicated that both maternal and paternal responsivity were positively associated with child talkativeness and lexical diversity. Parental responsivity, however, was not associated with child syntactic complexity. Findings also indicated that older children and children with higher levels of adaptive behavior had parents who used higher rates of responsive behaviors; these children also had higher levels of talkativeness, lexical diversity, and syntactic complexity. Additionally, fathers used higher rates of behavior management strategies compared to mothers, and this type of parental behavior was not associated with child language performance. The findings of this dissertation advance our understanding of family relationships in families of children with FXS as well as features of dyadic relationships within families that promote optimal outcomes.

                    Cover page: An Examination of Family Dynamics, Parental Responsivity, and Child Communication in Fragile X Syndrome
                    • Article
                    • Peer Reviewed
                    UC Davis Previously Published Works (2023)

                    Introduction

                    Telehealth is an important tool in helping to provide services for hard-to-reach populations. One population that might benefit from telehealth are individuals with fragile X syndrome (FXS). Although FXS is the leading inherited cause of intellectual disability, it is nonetheless a low incidence disorder. Individuals with FXS and their families are involved in research studies, clinical trials and receive interventions - many of which are only offered in a few locations in the United States and thus, not easily accessible to many families. The current project explored the feasibility of using telehealth procedures to collect multimodal behavioural and psychological assessment data from these families.

                    Methods

                    Participation in the current study involved online surveys, measures of physiological indices of stress, live interviews and observations of mother-child interactions conducted via distance videoconferencing using the family's own technology when possible. Across all modes of data collection, we obtained information regarding the feasibility of participating entirely via distance by documenting missing data as well as each mother's overall impression of participating via distance.

                    Results

                    Our telehealth procedures were successfully implemented across a wide range of technology platforms with limited difficulty, and we documented little missing data due to technology-related challenges. Perhaps most importantly, however, our sample of mothers reported high satisfaction with participating via distance.

                    Discussion

                    These findings suggest that a wide range of services and types of assessments may be amenable to telehealth procedures. Further, the findings have immediate applications as the field shifts towards telehealth due to the coronavirus disease 2019 (COVID-19) pandemic.
                      Cover page: Exploring the feasibility of collecting multimodal multiperson assessment data via distance in families affected by fragile X syndrome
                      Top