PROJECT SUMMARY Gaps in academic achievement lead to gross racial disparities in mental health, physical health, and substance use and abuse and compound inequalities, threatening individual as well as social and national economic well-being. Black children represent one group at substantial risk for educational underachievement due to dialect mismatch effects that can hamper reading performance: Ninety percent Black children speak African American English (AAE) as their primary dialect, yet the learning environment in the school is that of Mainstream American English (MAE). Dialect mismatch effects have been tested using offline measures of language production and comprehension in Black children, ages 5- to 8 years, when reading skills are coming online. However, language production measures cannot expose subtle interruptions in AAE speakers’ comprehension as they learn in MAE. Thus, there is a critical need for measures sensitive to moment-by-moment language processing. In the absence of such methods, the promise of understanding potential educational costs of dialect mismatch effects will likely remain elusive. Our central hypothesis is that school-aged Black children with stronger language skills will be sensitive to violations of phonology and grammar in AAE and MAE, but that school-age children with weaker language skills will show little sensitivity to such violations. Our hypothesis has been formulated based on extant research linking children’s processing speed with language ability. Further, our own pilot data, conducted with White speakers of MAE, demonstrated statistically significant differences in time spent looking at stimuli when language input does or does not contain linguistic violations. We plan to attain the overall objective by pursing the following specific aims: (1) to apply eye-tracking to evaluate sensitivities to violations of phonology and grammar in both MAE and AAE, in 7-year-old Black children; and (2) to determine how well eye-tracking profiles align with measures of language production commonly used in clinical practice. At the completion of the proposed project, our expected outcomes are to have identified key dialect detection profiles of typically-developing Black children. These results will provide a foundational evidence base on dialect detection in young Black children, supplying insights into normative development that have potential applications to the treatment of developmental language disorder.