The link between vision and reading: A language-agnostic window into heterogeneity in early reading development.

Despite decades of research, the role of visual processing in learning to read remains contested—largely due to small, homogenous samples and the lack of reliable tools to capture the true heterogeneity of reading development. In this study, we administered theory-driven, carefully validated measures of rapid visual processing to a large, socioeconomically and linguistically diverse cohort of kindergarten and first-grade children in California public schools (N ~ 1200). These visual measures proved to be equitable—performance did not vary by home language or socioeconomic status—and independently accounted for 12–16% of the variance in reading outcomes. They were also significant predictors of reading risk at year-end and a year- later. Latent profile analysis revealed subgroups invisible to traditional screeners: children with strong language but poor visual skills who later struggled to read, and children with visual strengths who outperformed expectations despite phonological weaknesses. Integrating measures of rapid visual processing into early screening offers a promising path forward, towards more equitable, personalized interventions and a deeper understanding of reading development.