Markers of developmental surface dyslexia in a language (Italian) with high grapheme-phoneme correspondence

This article examines the characteristics of surface dyslexia in a language (Italian) with high grapheme-phoneme correspondence. The reading performances of four boys are reported. The most pervasive reading symptom was severe slowness, which was associated in some, but not all, cases with reduced text comprehension. All four dyslexics performed at chance level on a task requiring comprehension of homophonous words (Study I). Vocal reaction times to single words were delayed with respect to the controls and showed a clear word length effect (Study II). However, vocal reaction times to pictorial stimuli were normal (Study III). Eye movement recordings taken during reading indicated an increased number and a reduced amplitude of rightward saccades and longer fixation durations (Study IV). A test of letter recognition in central and peripheral vision indicated that the reading deficit could not be explained in terms of an abnormal attentional "window," as found in other cases of dyslexia (Study V). An analysis of the boys' cognitive skills (Study VI) indicated spared phonological awareness in three of four subjects; a severe deficit in rapid scanning of nonlinguistic stimuli was present in all of the subjects, Overall, these results indicate that parallel visual processing of words was impaired, and that the boys analyzed words sequentially, presumably through an orthographic-phonological conversion. This condition may be interpreted as surface dyslexia, even though the prominent characteristics of this syndrome are somewhat different in Italian than in other languages. In languages with "loose" relationships between graphemes and phonemes (e.g., English), when the phonological analysis of words is insufficient, a variety of errors is produced. In languages with considerably more regular grapheme-phoneme correspondence (e.g., Italian), the number of errors may be small since phonological reading is generally correct, and the most conspicuous symptom is slowness in reading.