This study examined adult perceptions of two developmental disabilities: dyslexia (DYX) and Intellectual Disability (ID). Participants (n=1258) recruited through Mechanical Turk answered survey questions pertaining to symptoms, views, and possible causes of DYX and ID compared with obesity (OB) as a comparison condition. Exploratory factor analysis revealed 5 distinct factors across all three conditions: (1) psychosocial causes, (2) external causes, (3) biological causes, (4) consequence, and (5) controllability. Ethnic, gender and parental status (parent or nonparent) differences towards DYX and ID perceptions were examined. Three-way ANOVAs indicated effects of ethnicity, gender, and parental status on perceptions. Males endorsed psychosocial and external causes more often than females. Those who self-identified as Asian viewed DYX and ID as more highly controllable in comparison to Whites. Additionally, results revealed a three-way interaction regarding controllability, which suggests that Asian fathers and Hispanic mothers more often believe that a child with DYX can control his/her condition. Understanding the public’s perceptions about developmental disorders helps distinguish accurate from erroneous beliefs. Furthermore, understanding differences that may exist in particular groups can help implement targeted actions to improve awareness, care, and interventions for families.

There is a long-standing debate about whether bilinguals have enhanced executive function abilities due to regularly managing two languages and thus constantly activating brain regions responsible for executive control. This dissertation presents four studies investigating the impact of bilingualism on executive function abilities. Chapter 1 provides an argument towards an integration of hotter executive function measures regarding the bilingual advantage debate. Chapter 2 used secondary data to analyze the development of bilingual children’s executive function overtime in a longitudinal study across several time points from ages five to seven. Findings indicate that bilingual and monolingual children are different in some ways, such as their rate of change on cognitive control. Additionally, teachers rated bilingual children as having better inhibitory control and attention skills at the start of kindergarten in comparison to monolingual children, which may be reflective of hot executive function skills. Chapter 3 expands upon the results of Chapter 2 by examining how the teachers rated eight-year-old children’s hot executive function skills, internalizing and externalizing problems and interpersonal skills. The results paralleled those found in Chapter 2. Next, Chapter 4 follows up and expands the prior studies through investigating hot executive function skills among bilingual undergraduates via a computerized executive function task that implements affective stimuli. Chapter 5 examines whether bilingual and monolingual children differ on hot and cool executive function tasks that differ on their interpersonal level (2 tasks that are interpersonal and 2 tasks that are intrapersonal) and furthermore how these tasks relate to a novel ecological hot executive function task. Our novel child friendly computerized executive function task with affective stimuli directly contrasts neutral stimuli of a pre-existing executive function task. Additionally, Chapter 5 includes extensive information regarding the child’s background, language experience and exposure. This collection of studies aims to provide evidence for how bilingualism relates to executive function using a holistic multimethod approach including, a longitudinal design, non-affective and affective executive function tasks, teacher reports and parent reports. Theoretical and methodological implications, as well as limitations of the studies in this dissertation are discussed.

The current dissertation examines the cognitive benefits of bilingualism and the possible mechanisms related to advanced cognition by which such benefits operate. Although older balanced bilinguals (proficient in two languages) display several cognitive advantages (Bialystok, 2001; Hakuta, 1987) when compared to monolinguals, less is known about when such benefits begin during early development. In an effort to examine potential advantages of early bilinguals, this dissertation utilizes a series of visual-spatial memory and executive functioning tasks. In addition, this dissertation investigates the influence of several methological factors on cognitive performance including socioeconomic status (SES), age, and language group. A robust finding from these experiments suggests having equal proficiency levels in two languages leads to success on tasks of visual-spatial memory, executive functioning inhibitory control, and executive functioning attentional control. This dissertation addresses these factors through the utilization of a low-SES population, a single early age group (four-year-olds), and two monolingual groups for comparison (English and Spanish).

Despite being studied for an entire century, non-verbal visuospatial skills in Dyslexia have not been comprehensively investigated. Studies have focused mainly on adolescents and adults, on aptitude rather than learning processes, and focused mainly on mental rotation and pattern recognition. In this work we highlight why a better understanding of visuospatial skills is capital to the development and support of young individuals with dyslexia, as a population with a very unique neurocognition. We also piloted an alternative research design to better address the gaps encountered in our review of the existing literature, and model a new approach to studying visuospatial skills in dyslexia. The results of our study indicate a difference in processing and learning between participants with and without dyslexia, as well as an interesting progression of the visuospatial skills tested across age.