Morphological priming in children: disentangling the effects of school-grade and reading skill

Masked priming studies have shown that readers decompose morphologically complex words (read+er). Interindividual differences have been suggested to affect this phenomenon. However, its development is poorly understood. We addressed this issue by taking a longitudinal approach that allows greater rigor in establishing the relationship between grade, reading skill, and morphological priming. A masked priming lexical decision task with suffixed words (kleidchen-KLEID), suffixed nonwords (kleidtum-KLEID), non-suffixed nonwords (kleidekt-KLEID) and unrelated primes (träumerei-KLEID) was administered to 98 children in grade 2, and again in grade 3 and 4 of elementary school. Reading skill was measured at each testing point. Grade and reading skill were associated with distinct patterns of priming: all priming effects increased with reading skill, whereas priming from non-suffixed nonwords decreased with grade. This suggests that the ability to identify stems can be associated with reading skills, while sensitivity to affixes is acquired over grades.