Longitudinal Study of Neuropsychological Functioning and Internalizing Symptoms in Youth With Spina Bifida: Social Competence as a Mediator

Youth with spina bifida (SB) have been identified as being at risk for psychosocial difficulties, including poor social competence and increased internalizing symptoms (Ammerman et al., 1998; Holmbeck & Devine, 2010; Holmbeck et al., 2003, 2010). SB is a congenital birth defect caused by incomplete closure of the neural tube during the early weeks of gestation. In addition to serious health complications, such as paralyzed lower extremities, bladder and bowel incontinence, and seizures, many individuals with SB develop hydrocephalus, which is commonly treated with a shunt at birth (Holmbeck et al., 2003). The purpose of the current study is to test the utility of a longitudinal meditational model (see Figure 1) that posits associations between neuropsychological functioning and internalizing symptoms as mediated by social competence. Figure 1. The effect of neuropsychological functioning on internalizing symptoms, as mediated by social competence. Previous work has revealed that youth with SB are at higher risk for psychological maladjustment compared with typically developing youth (Holmbeck et al., 2003), and research on predictors of internalizing symptoms in this population has emerged as an important area of inquiry (e.g., Bellin et al., 2010). In particular, neuropsychological functioning (i.e., executive dysfunction, performance attention skills, reported attention problems, and IQ) may be a salient domain that impacts internalizing symptoms in youth with SB. Due to brain malformations characteristic of SB and the consequences of shunt placement at birth (i.e., shunt infections and replacement), the majority of youth with SB display mild to moderate cognitive impairments, such as executive dysfunction, inattention, and impaired intellectual functioning (Rose & Holmbeck, 2007). Researchers investigating the link between neuropsychological functioning and internalizing symptoms have proposed a biopsychosocial model of chronic illness, which suggests that youth who have executive function deficits may exhibit difficulties shifting attention from stressful stimuli and, thus, may be at an increased risk for internalizing symptoms (Compas & Boyer, 2001). In support of this model, executive function deficits that are common in SB (i.e., difficulties in the areas of metacognition, encoding, focusing, and shifting attention; Loss, Yeates, & Enrile, 1998; Zabel et al., 2013) have been linked to internalizing symptoms (Kelly et al., 2012). Further, while research to date has not examined the impact of inattention on internalizing symptoms in this population, inattention has been linked to greater internalizing symptoms in other pediatric populations (e.g., children with chronic fatigue syndrome; Tucker, Haig-Ferguson, Eaton, & Crawley, 2011). Similarly, low verbal IQ has been linked to greater internalizing symptoms (i.e., anxiety) in youth with epilepsy (Caplan et al., 2005). However, there have been variable results with regard to the link between IQ and internalizing symptoms in youth with SB. One study found that verbal IQ is not a significant predictor of depressive symptoms (Schellinger, Holmbeck, Essner, & Alvarez, 2012), whereas another study found that lower verbal IQ is predictive of poorer psychosocial adaptation (Coakley, Holmbeck, & Bryant, 2006). Although studies examining associations between neuropsychological functioning and internalizing symptoms in pediatric populations have steadily increased in the past decade, less attention has been paid to underlying mechanisms, or mediators, of this association. In particular, the link between neuropsychological functioning and internalizing symptoms may be mediated by social competence, such that neuropsychological functioning may impact social competence, which, in turn, may impact internalizing symptoms. Previous research on youth with SB has identified significant social deficits that map onto Cavell’s (1990) tri-component model of social competence: (1) social adjustment (e.g., fewer close friendships; Devine, Holmbeck, Gayes, & Purnell, 2012), (2) social performance (e.g., social immaturity, withdrawal, and passivity; Ammerman et al., 1988; Holmbeck et al., 2003; Rose & Holmbeck, 2007), and (3) social skills (e.g., inappropriate sociability and verbosity; Burmeister et al., 2005). Highlighting the impact of neuropsychological functioning on social competence, Rose and Holmbeck (2007) found that both performance- and questionnaire-based measures of executive dysfunction contributed to social competence impairment in youth with SB. Further, youth with SB exhibiting deficits in problem solving and planning may have difficulty performing appropriate social behavior, such as communicating necessary information to peers (i.e., social language) and understanding the rules of social engagement (Landry, Robinson, Copeland, & Garner, 1993). Symptoms of inattention may also impact social competence and internalizing symptoms in youth with SB. Individuals with SB tend to exhibit attention problems that are similar to children with attention-deficit/hyperactivity disorder (ADHD), including high distractibility, poor organization of materials, and difficulty staying on task (Burmeister et al., 2005). Children with ADHD often have peer conflicts, are less popular with peers, experience higher levels of peer rejection, and lack close friendships. These social difficulties evident in children with ADHD appear to increase their risk of later psychopathology (Nijmeijer et al., 2008). Similarly, preliminary findings have revealed that adolescents with SB have enduring attention problems that are associated with difficulties with social competence (Rose & Holmbeck, 2007), such as fewer friendships and a lower level of closeness with same-age peers (Holmbeck et al., 2010). Further, with regard to the link between IQ and social competence, children with intellectual disabilities may show decreased social competence, including poor peer relationships, social withdrawal, and delayed development of social skills (e.g., difficulties with communication and using appropriate social interaction strategies; Bellanti & Bierman, 2000; Guralnick, 1999; Zion & Jenvey, 2011). Finally, the connection between social competence and internalizing symptoms has shown strong and consistent support in the literature. Social competence difficulties, such as peer rejection, have been linked to increases in internalizing symptoms in several pediatric populations, including children with inflammatory bowel disease (Greenley et al., 2010), glycogen storage disease type 1 (Storch et al., 2008), pediatric pain (i.e., disease- and non-disease-related pain; Claar & Walker, 2006; Gauntlett-Gilbert & Eccelston, 2007; Peterson & Palermo, 2004; Sandstrom & Schanberg, 2004), and youth with SB (Essner, Murray, & Holmbeck, 2014). Youth may experience increased internalizing symptoms as a result of poor social competency for a variety of reasons, including limited social interactions, feelings of low self-worth related to peer status, or increased anxiety in social situations. While studies have begun to investigate associations among neuropsychological functioning, social competence, and internalizing symptoms in youth with SB, these domains have yet to be tested within one unified model. Thus, the purpose of this study was to examine the utility of a model of neuropsychological functioning (i.e., executive dysfunction, performance attention skills, reported attention problems, and IQ), social competence, and internalizing symptoms in youth with SB (see Figure 1). It was expected that social competence would mediate the relationship between neuropsychological functioning and internalizing symptoms in youth with SB. Specifically, executive dysfunction, inattention, and lower IQ were expected to predict lower levels of social competence that, in turn, would predict increased internalizing symptoms in this population.