Phonological and graphotactic influences on spellers' decisions about consonant doubling

Even adults sometimes have difficulty choosing between single- and double-letter spellings, as in spinet versus spinnet. The present study examined the phonological and graphotactic factors that influence adults' use of single versus double medial consonants in the spelling of nonwords. We tested 111 adults from a community sample who varied widely in spelling ability. Better spellers were more affected than less good spellers by phonological context in that they were more likely to double consonants after short vowels and less likely to double consonants after long vowels. Although descriptions of the English writing system focus on the role of phonology in determining use of single versus double consonants, participants were also influenced by graphotactic context. There was an effect of preceding graphotactic context, such that spellers were less likely to use a double consonant when they spelled the preceding vowel with more than one letter than when they spelled it with one letter. There was also an effect of following graphotactic context, such that doubling rate varied with the letters that the participant used at the end of the nonword. These graphotactic influences did not differ significantly in strength across the range of spelling ability in our study. Discussion focuses on the role of statistical learning in the learning of spelling patterns, especially those patterns that are not explicitly taught.