What Do Spelling Errors Tell Us About Language Knowledge?

Like reading, spelling is a written language skill that draws upon an individual's repertoire of linguistic knowledge, including phonological awareness, and knowledge of orthography, vocabulary, morphological and semantic relationships; and mental orthographic images (Apel & Masterson, 2001; Apel, Masterson, & Niessen, 2004). Each of these areas of linguistic or "word study" knowledge contributes to spelling success (Treiman & Bourassa, 2000) and a deficit in any one of these areas of word study knowledge will manifest as a specific pattern of misspelling. Accordingly, the analysis of an individual's spelling errors can be used to identify underlying linguistic deficits.

The Language of Spelling

Phonological Awareness

Individuals rely upon the phonological awareness skills of phoneme segmentation, sequencing, discrimination, and identification during the spelling or "encoding" process. They use phonological segmentation skills when spelling by breaking down words into smaller units such as syllables and phonemes then linking these smaller units to their written forms. Individuals also use sound sequencing skills to map the letters to sounds in the correct order and they use phoneme discrimination and identification skills to perceive differences between speech sounds (e.g., between the short vowel e and short vowel i sounds) and to recognize that a difference in sound signals a difference in meaning.

Orthographic Knowledge

Individuals also draw upon their orthographic knowledge during the encoding process. Specifically, individuals draw upon their knowledge of sound-letter relationships and knowledge of letter patterns and conventional spelling rules to convert spoken language to written form (Ehri, 2000; Treiman & Bourassa, 2000). Orthographic knowledge includes knowledge of specific letter-sound relationships (e.g., the / k /sound can be represented by the letters c, k, ck, cc, lk, ch, que); knowing which letter patterns are acceptable (e.g., the / k /sound is almost always spelled with the letter k at the end of a word after a long vowel sound); and understanding sound, syllable, and word position constraints on spelling patterns (e.g., the / k /sound at the beginning of a word is never spelled with the letters ck, cc, lk).

Vocabulary

Individuals use vocabulary knowledge to accurately store and retrieve the correct spelling of words. The knowledge of word meaning is particularly important for the correct spelling of homophone words (e.g., bare and bear). Vocabulary knowledge is also helpful to correctly spell the wh consonant digraph because the / w / sound at the beginning of question words (what, where, when, why, which) is always spelled with the letters wh.

Morphological Knowledge & Semantic Relationships

Individuals also rely upon their morphological knowledge and knowledge of semantic relationships when spelling inflected or derived forms of words (Carlisle, 1995). Specifically, individuals rely upon their knowledge of letter-meaning relationships of individual morphemes (i.e., suffixes, prefixes, base words, and word roots), their understanding of semantic relationships between a base word and related words, and their knowledge of modification rules when adding prefixes and suffixes.