Early-Adult Executive Functions in Girls with and without Childhood ADHD

Executive functions (EFs) are neuropsychological constructs that help individuals perform complex, future-oriented actions that are necessary for successful performance of activities in academic and employment settings and in social interactions. Research on children with attention deficit hyperactivity disorder (ADHD) demonstrates that deficits in EFs are linked with a variety of functional impairments. However, there is limited research on the EF trajectories of girls with ADHD as they develop—and their associated impairments. Thus, my aim for this dissertation was to examine trajectories of EF deficits from childhood to emerging adulthood (i.e., ages 23-29) in an all-female ADHD sample, along with the impact these deficits may have on externalizing and internalizing behaviors and academic achievement by this period of emerging adulthood. For this investigation I utilized a sample of 140 girls diagnosed with ADHD and 88 comparison girls matched for age and ethnicity (Wave 1; mean age = 9.5 years). 209 (92%) participated in five-year follow-up assessments (Wave 2; mean age = 14.1); 216 (95%) participated in 10-year follow-up assessments (Wave 3; mean age = 19.6); and 211 (93%) participated in the 16-year follow-up assessments (Wave 4; mean age = 25.6). EF measurements assessing response inhibition, working memory, visual discrimination, and global EF were administered at all four waves. At Wave 4 the young women self-reported on their internalizing, externalizing, and depressive symptoms; parental reports on internalizing and externalizing symptoms and objective measures of reading and math were also utilized. With the exception of Wave 1 response inhibition, the young women with ADHD performed worse on all EF measures at all waves, when compared to the matched subsample of women without ADHD histories. They also had poorer internalizing, externalizing, and depressive symptoms as well as poorer academic achievement. Growth curve modeling indicated that, even though all women experienced absolute increases in EF performance across waves, the women with histories of ADHD persistently lagged behind comparison women at all measurement points. In addition, young women with histories of ADHD had steeper rates of improvement than their comparison peers on the global executive functioning task, yet the opposite pattern was observed for the visual discrimination/inhibitory response task, on which comparison peers demonstrated steeper improvements. Importantly, the trajectory of working memory performance predicted self-reported externalizing behavior by emerging adulthood. In addition, improvements in the young women’s performance in both working memory and visual discrimination/inhibition were associated with adult reading and math achievement. Moreover, higher levels of Wave 4 working memory were associated with higher concurrent levels of reading achievement in the ADHD than the comparison sample. Overall, these findings contribute to greater understanding of executive functioning in young women with ADHD and suggest that EF deficits should be considered when developing and implementing treatments for ADHD through emerging adulthood. Future research should be aimed at understanding the mechanisms behind the associations observed