Comparing Behavioral and Parent-Report Measures of Executive Functioning in Deaf and Typically Hearing Children

Executive functioning (EF) is a multidimensional aspect of development that encompasses various mental skills. Children’s utilization of inhibition, in particular, has proven to be one of the most important determinants of academic success. How deafness in children impacts their EF abilities is a question that remains divisive within deaf studies. Some suggest that auditory deprivation is a direct cause of poor EF, while others posit reduced or insufficient language experience that deaf children live with harms their EF development. We sought to explore this question further with a participant sample from our larger SLaM (Study of Language and Math) project. A total of 88 participants consisting of deaf/hard-of-hearing (DHH) (n = 67) and typically hearing participants (n = 21) ages 3;1-7;6 were divided into separate language timing (Early vs. Later) and language modality (ASL vs. English) groups. Scores on a behavioral, non-standardized measure of EF (Opposites task) and a standardized parental report measure (BRIEF-P: Behavior Rating Inventory of Executive Function Preschool) were compared separately across timing and modality groups. Additionally, potential relationships between these measurements of EF were explored. We found that earlier access to language positively impacts EF abilities on the BRIEF-P only. When language modality was considered alone, it had no apparent influence on EF abilities for either of the two tasks. Our results corroborate previous findings suggesting that behavioral non-standardized measures and standardized measures of EF do not significantly correlate with one another (Beer, Kronenberger, Castellanos, Colson, Henning, and Pisoni, 2014). COMPARING MEASURES OF EF IN DEAF & TYPICALLY HEARING CHILDREN ​5 Introduction Executive Functioning (EF) Executive functioning (EF) encompasses a spectrum of skills and abilities that are necessary to accomplish a wide variety of tasks. Some of these skills include inhibition, cognitive flexibility, planning, goal-directed behavior, utilizing working memory, and utilizing new responses (Henry, Messer, and Nash, 2012). EF consists of mental processes used to direct thought and behavior that are necessary for children’s development and success in school. EF is also essential to social functioning or aiding children in their ability to manage challenging social situations that require them to regulate their emotions, inhibit hasty actions, and comply with school rules and guidelines. Development of EF skills early in life is certainly a predictor for school readiness but has also shown to be a predictor of later academic success, such as preparedness for the transition into middle school (Hunter & Sparrow, 2012). Ties Between Executive Functioning and Language Experience in Early Childhood Research on inhibition, in particular, has demonstrated that it provides the strongest contribution to math abilities. Inhibition is a mental skill that requires self-regulation or engaging in internal controls to restrain and monitor certain actions and behaviors. Inhibition, effortful control, and nonverbal problem-solving skills are known for predicting achievement in mathematics in kindergarten and beyond. Spatial working memory has shown to be associated with children’s early counting ability and math achievement as late as middle school. These processes are directly tied to the functional connectivity of multiple underlying brain systems used for language processing, perception, and production (Hunter & Sparrow, 2012). Marschark, COMPARING MEASURES OF EF IN DEAF & TYPICALLY HEARING CHILDREN ​6 Pisoni, Conway, Kronenberger, Henning, and Anaya (2012) argue that these EF processes contribute to variance observed in populations with regard to speech and language outcomes beyond conventional demographic, medical, and educational factors. Additionally, they found that several domain-general neurocognitive processes related to EF and cognitive control processes, including working memory and inhibition, are strongly associated with language outcome measures. Hypotheses about Language Experience and Executive Functioning This association between EF and language provides a potential explanation for why people with lower language abilities/delayed language exposure (also known as “language deprivation”) display EF deficits. Both timing and quality of language access during the critical period of language acquisition are essential for healthy brain development (Hall, Levin, and Anderson, 2017). Many deaf and hard-of-hearing (DHH) individuals have experienced language deprivation and deaf children perform poorly on tasks that require EF. In other words, underdevelopment of language in deaf children could be negatively impacting their EF skills, as language is positively correlated with EF in both deaf and hearing children (Beer et al., 2014; Figueras, Edwards, and Langdon, 2008; Henry et al., 2012). Previous research has demonstrated that DHH children tend to perform poorly on tasks requiring EF and fall behind their hearing peers. A 2014 study found that deficiencies in EF in older children with CIs (cochlear implantations) begin to develop as early as preschool years. This longitudinal study involved 24 preschoolers who received CIs before 36 months of age and 21 preschoolers with normal hearing. Children were tested on normed measures of working memory, inhibition-concentration, and organization-integration, and parents completed the BRIEF-P, which is a normed COMPARING MEASURES OF EF IN DEAF & TYPICALLY HEARING CHILDREN ​7 parent-report measure of children’s behaviors. The study demonstrated that preschoolers with CIs showed significantly poorer performance on tasks requiring inhibition-concentration and working memory than their peers with normal hearing. Interestingly, although parents reported more difficulty in daily circumstances utilizing working memory and planning/organizing skills, it was not significantly correlated with behaviorally-based performance measures of executive functioning (Beer et al., 2014). Literature is divided on whether or not there is a direct, causal relationship between auditory deprivation and EF abilities. Auditory deprivation refers to the specific lack of auditory input that occurs with deafness, while language deprivation refers to the lack of linguistic input that deaf children often face during their formative early childhood years. Proponents of this hypothesis suggest that hearing provides necessary exposure to serially ordered events and because sound is a temporal and sequential signal, it provides a “scaffolding” or supporting framework that humans use to interpret and process sequential information (Conway, Pisoni, and Kronenberger, 2009). The language deprivation hypothesis claims that exposure, access, and reinforcement of language are all important to EF. A number of researchers argue that deafness may not be a direct cause of poor EF in children, but that language deprivation may contribute to a lack of EF skills. In other words, the lack of EF in deaf children may result as a secondary consequence of hearing loss. This hypothesis is supported by research that has found data to be entirely consistent with the idea that early access to language is crucial to the development of EF abilities (Botting et al., 2017; Figueras et al., 2008; Hall, Eigsti, Bortfeld, and Lillo-Martin, 2018). These COMPARING MEASURES OF EF IN DEAF & TYPICALLY HEARING CHILDREN ​8 researchers argue that there is no strong evidence to suggest that auditory development alone has a detrimental effect on EF development. The lack of clarity on how language acquisition impacts EF can be attributed to multiple factors. Firstly, the developmental trajectory of EF has historically been difficult to measure due to the complex nature and brain processes behind it. Kalback (2004) claims that neuropsychological perspectives on the executive system have focused on specific behavior “localization” which has led to an impairment-focused theory. This impairment-focused theory has allowed neuropsychologists to view and assess the operation of the executive system as a developmental construct. It must be noted that despite the fact that the executive system operates mainly from the frontal lobes of the human cortex, it works in association with other areas of the cortex. This gives rise to the complex nature of EF and the resulting difficulties in studying this construct. There are also clear research deficits in studying how language acquisition impacts EF in deaf and hard-of-hearing children. These deficits can be attributed to the fact that there is a substantial variation in language instruction that deaf children receive. The vast majority of deaf children have hearing parents as opposed to deaf parents and may receive very little American Sign Language (ASL) instruction (Kalback, 2004). In addition, there are methodological limitations that create challenges in reaching conclusions on EF and language data. Some studies rely only on questionnaire data or one or two experimental tasks. Analyses are also limited by smaller sample sizes. The hearing status of parents is sometimes not reported despite it having an impact on children’s performance when children of deaf parents perform better on tasks (Botting et al., 2017). Despite these barriers, it must be noted that being born deaf is not necessarily a COMPARING MEASURES OF EF IN DEAF & TYPICALLY HEARING CHILDREN ​9 direct cause of language impairment. However, exposure to these environmental and physiological impediments, means that deaf children are at higher risk for language difficulties than typically hearing children (Kalback, 2004). Study of Language and Math (SLaM) SLaM Project 1 Hypotheses & Results Project 1 of the SLaM study investigated how language impacts children’s development of number concepts. The study concluded that the timing of language exposure provides the foundation for basic number conce