Simple morphological spelling rules are not always used: Individual differences in children and adults

The English spelling system has a variety of rules and exceptions, but both theoretical and empirical accounts have generally concluded that by about age 9 or 10, children master the morphological rule that regular plural nouns (e.g., socks) and third-person singular present verbs (e.g., lacks) are spelled with the inflectional ending -s. In three experiments, however, we found that when forced to rely exclusively on morphological cues, only a minority of primary school children, secondary school children, and even adults performed significantly above chance at choosing the appropriate spelling for novel words presented as inflected or uninflected nouns and verbs. Further, significantly above-chance performance was more common in adults who had attended school until age 18, compared to age 16. We conclude that many spellers, especially those who do not go on to tertiary education, never learn some simple morphological spelling rules, and instead rely on a store of individual word-specific spellings.