Error dynamics as a marker of reading efficiency development: Insights from lexical decision performance in young readers

Understanding reading development requires investigating how visual word recognition capacities develop, particularly through lexical decision tasks. Traditionally, accuracy and reaction times (RTs) are analysed separately, overlooking their interaction, which provides crucial insights into performance. This study proposes a novel framework, hypothesizing that error dynamics (i.e., error distribution through RTs) could be an objective marker of reading efficiency. To test this hypothesis, the study investigated the relationship between reading skills in learning-to-read children and the dynamics of lexical decision errors. Lexical decision performance was analysed in 56 French-speaking children (22 Grade 1 and 34 Grade 2, 36 females). Two complementary methodologies were employed: RTs comparison between correct and incorrect responses and Conditional Accuracy Functions (CAFs) to evaluate accuracy as a function of RTs. Results showed that pseudoword errors were faster than correct responses whereas word errors were slower than correct responses. Of importance, fewer slow word errors and more fast pseudoword errors correlated with reading skills. The findings suggested that as reading skills improve, error dynamics would progressively shift from slow word errors to fast pseudoword errors. This study demonstrated that integrating accuracy and RTs via error dynamics analysis could provide objective markers of reading development. Crucially, it highlights a novel developmental index of reading skills through the shift of error patterns, offering a promising avenue for early identification of reading difficulties.