Phonological generalizations in dyslexia: the phonological grammar may not be impaired.

Dyslexia is commonly attributed to a phonological deficit, but whether it effectively compromises the phonological grammar or lower level systems is rarely explored. To address this question, we gauge the sensitivity of dyslexics to grammatical phonological restrictions on spoken onset clusters (e.g., bl in block). Across languages, certain onsets are preferred to others (e.g., blif ≻ bnif ≻ bdif, where ≻ indicates a preference). Here, we show that dyslexic participants (adult native speakers of Hebrew) are fully sensitive to these phonological restrictions, and they extend them irrespective of whether the onsets are attested in their language (e.g., bnif vs. bdif) or unattested (e.g., mlif vs. mdif). Dyslexics, however, showed reduced sensitivity to phonetic contrasts (e.g., blif vs. belif; ba vs. pa). Together, these results suggest that the known difficulties of dyslexics in speech processing could emanate not from the phonological grammar, but rather from lower level impairments to acoustic/phonetic encoding, lexical storage, and retrieval.