Abstract: OBJECTIVE: To examine the effect of word length and several sublexical, and lexico-semantic variables on the reading of Italian children with a developmental reading deficit. BACKGROUND: Previous studies indicated the role of word length in transparent orthographies. However, several factors that may interact with word length were not controlled for. METHODS: Seventeen impaired and 34 skilled sixth-grade readers were presented words of different lengths, matched for initial phoneme, bigram frequency, word frequency, age of acquisition, and imageability. Participants were asked to read aloud, as quickly and as accurately as possible. Reaction times at the onset of pronunciation and mispronunciations were recorded. RESULTS: Impaired readers' reaction times indicated a marked effect of word length; in skilled readers, there was no length effect for short words but, rather, a monotonic increase from 6-letter words on. Regression analyses confirmed the role of word length and indicated the influence of word frequency (similar in impaired and skilled readers). No other variables predicted reading latencies. CONCLUSIONS: Word length differentially influenced word recognition in impaired versus skilled readers, irrespective of the action of (potentially interfering) sublexical, lexical, and semantic variables. It is proposed that the locus of the length effect is at a perceptual level of analysis. The independent influence of word frequency on the reading performance of both groups of participants indicates the sparing of lexical activation in impaired readers.
Abstract: Participants report briefly-presented words more accurately when two copies are presented, one in the left visual field (LVF) and another in the right visual field (RVF), than when only a single copy is presented. This effect is known as the 'redundant bilateral advantage' and has been interpreted as evidence for interhemispheric cooperation. We investigated the redundant bilateral advantage in dyslexic adults and matched controls as a means of assessing communication between the hemispheres in dyslexia. Consistent with previous research, normal adult readers in Experiment 1 showed significantly higher accuracy on a word report task when identical word stimuli were presented bilaterally, compared to unilateral RVF or LVF presentation. Dyslexics, however, did not show the bilateral advantage. In Experiment 2, words were presented above fixation, below fixation or in both positions. In this experiment both dyslexics and controls benefited from the redundant presentation. Experiment 3 combined whole words in one visual field with word fragments in the other visual field (the initial and final letters separated by spaces). Controls showed a bilateral advantage but dyslexics did not. In Experiments 1 and 3, the dyslexics showed significantly lower accuracy for LVF trials than controls, but the groups did not differ for RVF trials. The findings suggest that dyslexics have a problem of interhemispheric integration and not a general problem of processing two lexical inputs simultaneously.
Abstract: Italian is a language with a transparent orthography in which printed words can be translated into the correct sequence of phonemes using a limited set of rules. The rules of letter-sound conversion are, however, simpler for some letters than for others: The pronunciations of sequences involving the letters c and g are determined by complex (i.e., context-sensitive) rules that depend on the letters that follow them. In this article, we report two experiments in which Italian participants read aloud words containing simple or complex letter-sound conversion rules. In Experiment 1, we found that words containing complex rules were read more slowly than words containing simple, noncontextual rules. In Experiment 2, we found that the effect of rule complexity on naming speed held for low-frequency words but not high-frequency words. The results are interpreted in terms of a dual-route model in which rule complexity effects arise from sublexical procedures that are more involved in reading low-frequency words than high-frequency words. The experimental material used in this study may be downloaded from www.psychonomic.org/archive.
Abstract: Italian dyslexic children are characterized by a pervasive reading speed deficit, with relatively preserved accuracy. This pattern has been associated with predominant use of the nonlexical reading procedure. However, there is no evidence of a deficit in the lexical route of Italian dyslexics. We investigated both lexical and nonlexical reading procedures in dyslexic children through two marker effects, namely, the word frequency effect and the effect of contextual grapheme-to-phoneme conversion rules. Although dyslexics were slower and less accurate than controls, they were affected by word frequency, grapheme contextuality, and their interaction in a similar manner as average readers. These results show the use of lexical reading in Italian dyslexics, and refute the claim of a deficit in whole-word processing with consequent over-reliance on the nonlexical route.
Abstract: The CFVlexvar.xls database includes imageability, frequency, and grammatical properties of the first words acquired by Italian children. For each of 519 words that are known by children 18-30 months of age (taken from Caselli & Casadio's, 1995, Italian version of the MacArthur Communicative Development Inventory), new values of imageability are provided and values for age of acquisition, child written frequency, and adult written and spoken frequency are included. In this article, correlations among the variables are discussed and the words are grouped into grammatical categories. The results show that words acquired early have imageable referents, are frequently used in the texts read and written by elementary school children, and are frequent in adult written and spoken language. Nouns are acquired earlier and are more imageable than both verbs and adjectives. The composition in grammatical categories of the child's first vocabulary reflects the composition of adult vocabulary. The full set of these norms can be downloaded from www.psychonomic.org/archive/.
Abstract: The present study describes normative measures for 626 Italian simple nouns. The database (LEXVAR.XLS) is freely available for down-loading on the Web site http://wwwistc.ip.rm.cnr.it/materia/database/. For each of the 626 nouns, values for the following variables are reported: age of acquisition, familiarity, imageability, concreteness, adult written frequency, child written frequency, adult spoken frequency, number of orthographic neighbors, mean bigram frequency, length in syllables, and length in letters. A classification of lexical stress and of the type of word-initial phoneme is also provided. The intercorrelations among the variables, a factor analysis, and the effects of variables and of the extracted factors on word naming are reported. Naming latencies were affected primarily by a factor including word length and neighborhood size and by a word frequency factor. Neither a semantic factor including imageability, concreteness, and age of acquisition nor a factor defined by mean bigram frequency had significant effects on pronunciation times. These results hold for a language with shallow orthography, like Italian, for which lexical nonsemantic properties have been shown to affect reading aloud. These norms are useful in a variety of research areas involving the manipulation and control of stimulus attributes.
Abstract: Results from two separate norming studies of lexical access in Italian were merged, permitting a comparison of word-reading and picture-naming latencies and the factors that predict each one for an overlapping subsample of 128 common nouns. Factor analysis of shared lexical predictors yielded four latent variables: a frequency factor, a semantic factor, a length factor, and a final factor dominated by frication on the initial phoneme. Age of acquisition (AoA) loaded highly on the first two factors, suggesting that it can be split into separate sources of variance. Regression analyses using factor scores as predictors showed that word reading and picture naming are both influenced by the frequency/AoA factor. The semantics/AoA factor influenced only picture naming, whereas the length and frication factors influenced only word reading. Generalizability of these results to other languages is discussed, including potential effects of cross-language differences in orthographic transparency.
