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IntroductionExecutive functions (EFs) are linked to positive outcomes across the lifespan. Yet, methodological challenges have prevented precise understanding of the developmental trajectory of their organization.MethodsWe introduce novel methods to address challenges for both measuring and modeling EFs using an accelerated longitudinal design with a large, diverse sample of students in middle childhood (N = 1,286; ages 8 to 14). We used eight adaptive assessments hypothesized to measure three EFs, working memory, context monitoring, and interference resolution. We deployed adaptive assessments to equate EF challenge across ages and a data-driven, network analytic approach to reveal the evolving diversity of EFs while simultaneously accounting for their unity.Results and discussionUsing this methodological paradigm shift brought new precision and clarity to the development of these EFs, showing these eight tasks are organized into three stable components by age 10, but refinement of composition of these components continues through at least age 14.

The ability to learn second language speech sound categories declines during development. We examined this phenomenon by studying the mismatch negativity (MMN) to the /r/ - /l/ distinction in native English speakers and learners of English as a second language who are native speakers of Japanese. Previous studies have suggested that the MMN is remarkably plastic when evaluated as a waveform at a central electrode. We replicated this finding: analyses of the MMN at a typical electrode location (Fz) revealed only small, nonsignificant differences between groups, despite large behavioral differences in the ability to discriminate these sounds from one another. Topographic analyses, however, revealed reliable differences in lateralization of the MMN, such that native English speakers’ responses were left-lateralized relative to native Japanese speakers’ responses.

Enhanced N170 ERP responses to both faces and visual words raises questions about category specific processing mechanisms during early perception and their neural basis. Topographic differences across word and face N170s might suggest a form of category specific processing in early perception - the word N170 is consistently left lateralized, while less consistent evidence suggests a right lateralization for the face N170. Additionally, the face N170 shows a reduction in amplitude across consecutive unique faces, a form of habituation that might differ across studies thereby helping to explain inconsistencies in lateralization. This effect remains unexplored for visual words. The current study directly contrasts N170 responses to words and faces within the same subjects, examining both category-level habituation and lateralization effects. ERP responses to a series of different faces and words were collected under two contexts: blocks that alternated faces and words versus pure blocks designed to induce category level habituation. Global and occipito-temporal measures of N170 amplitude demonstrated an interaction between category (word, faces) and block context (alternating, pure). N170 amplitude demonstrated class level habituation for faces but not words. Furthermore, the pure block context diminished the right lateralization of the face N170, potentially pointing to class level habituation as a factor that might drive inconsistencies of right lateralization across different paradigms. No analogous effect for the word N170 was found, suggesting category specificity for this process. Taken together, these topographic and habituation effects suggest distinct forms of perceptual processing drive the face N170 and the visual word form N170.