Syllabic effects in Italian lexical access.

Two cross-modal priming experiments tested whether lexical access is constrained by syllabic structure in Italian. Results extend the available Italian data on the processing of stressed syllables showing that syllabic information restricts the set of candidates to those structurally consistent with the intended word (Experiment 1). Lexical access, however, takes place as soon as possible and it is not delayed till the incoming input corresponds to the first syllable of the word. And, the initial activated set includes candidates whose syllabic structure does not match the intended word (Experiment 2). The present data challenge the early hypothesis that in Romance languages syllables are the units for lexical access during spoken word recognition. The implications of the results for our understanding of the role of syllabic information in language processing are discussed.

The retrieval of syntactic and semantic information in the production of verbs.

In Italian, there are two aspectual auxiliaries: essere (to be) and avere (to have). According to the syntactic hypothesis, aspectual auxiliary assignment in Italian is a syntactic phenomenon. Using the picture-word interference paradigm, Experiment 1 tested the predictions of this view. Results failed to support the syntactic hypothesis but could be explained within a semantic framework: A verb's thematic grid is involved in aspectual auxiliary assignment. Experiment 2 tested this hypothesis. The findings corroborated the predictions. The evidence is interpreted as suggesting the involvement of thematic information in the assignment of the aspectual auxiliary during the production of Italian verbs.

The role of argument structure in the production of nouns and verbs.

The study reports an investigation on the role of argument structure complexity in the production of nouns and verbs in three Italian agrammatic patients. The patients, all showing a clear noun/verb dissociation in the assessment tests, were requested to produce either nouns or verbs in a picture naming task. Four sets of words were selected to be produced in the naming task: non-argumental nouns (e.g., medaglia-medal), argumental nouns (e.g., pianto-crying), one-place argument verbs (e.g., dormire-to sleep), and two-place argument verbs (e.g., sparare-to shoot). The performance of the three patients was almost identical. All made reliably fewer errors in the production of non-argumental nouns than in the production of verbs, thus replicating with the new materials the initially observed dissociation. Moreover, they made fewer errors with one-place than with two-place argument verbs, and with non-argumental than with argumental nouns. Finally, in contrast with the previously observed noun/verb dissociation, when their ability to produce argumental nouns and verbs was compared, no reliable difference was found. The results indicate that argument complexity may affect the ability of agrammatic patients to produce words. It is argued that since argument complexity is necessarily associated with verbs and only rarely with nouns, unless special attention is paid, argument complexity effects are easily confounded with grammatical class effects, possibly leading to erroneous interpretations of patients' performance.

Syllables in the processing of spoken Italian.

Five experiments explored the role of the syllable in the processing of spoken Italian. According to the syllabic hypothesis, the sublexical unit used by speakers of Romance languages to segment speech and access the lexicon is the syllable. However, languages with different degrees of acoustic-phonetic transparency give rise to syllabic effects that vary in robustness. It follows from this account that speakers of phonologically similar languages should behave in a similar way. By exploiting the similarities between Spanish and Italian, the authors tested this prediction in Experiments 1-4. Indeed, Italian listeners were found to produce syllabic effects similar to those observed in Spanish listeners. In Experiment 5, the predictions of the syllabic hypothesis with respect to lexical access were tested. The results corroborated these predictions. The findings are discussed in relation to current models of speech processing.

Left neglect dyslexia and the processing of neglected information.

A patient (ES) with a right fronto-temporo-parieto-occipital lesion, and left neglect dyslexia, is reported. ES performed reading and association tasks on written words, composed of two embedded words, one to the left and one to the right of the division point. The meaning of the whole stimulus differed from that of the embedded words, and could not be inferred from either of them. ES produced appropriate associations even to those stimuli on which she made neglect paralexic errors. This dissociation reflects a distinction between processes which use co-ordinate spatial systems and subserve perceptual awareness, impaired in hemineglect, and processes which do not. The latter analyse left-sided information to a large extent, without reaching awareness.

Automatic semantic facilitation in Alzheimer's disease.

To explore the nature of semantic deficit in Alzheimer's disease patients (AD patients) we compared two tasks that are known to be very different with respect to the type of attentional demand and conscious effort they require: lexical decision (automatic) in a semantic priming paradigm and semantic relatedness judgements (intentional). In order to minimise post-lexical facilitation we devised a semantic priming experiment that met an automatic condition as much as possible, and we selected patients without severe word recognition deficits. AD patients showed reduced accuracy in the semantic relatedness judgements as compared to controls. Some effect of priming was found, but this was weaker than in normals. AD patients also differed from controls on targets preceded by a nonlinguistic prime (neutral condition) where their reaction times were slower as compared to neutral condition.

Semantic priming in the pronunciation of words in two writing systems: Italian and English.

Semantic priming effects in naming Italian and English words were investigated. Experiments 1 and 2 were in Italian. In Experiment 1, the subjects named a target word, which was either associated with or unrelated to a preceding prime. The results showed semantic priming effects. However, in Experiment 2, in which the same materials occurred in a list that also included pseudowords, priming effects were obtained with the lexical decision task, but not with pronunciation. In Experiment 3, the inclusion of pseudowords in the materials prevented priming effects from occurring in Italian, but not in English. Finally, Experiment 4 indicated that, even in Italian, nonlexical reading was abandoned when a few of the to-be-pronounced items required lexical knowledge for correct stress assignment. The findings suggest that reading normally occurs lexically. The characteristics of the various writing systems, however, are relevant in determining the strategies that people may adopt in unusual circumstances.

Functional cerebral lateralisation; dichotomy or plurality?

Cartoon faces were presented tachistoscopically in the right and left visual fields, and required to be matched to a previously memorised target face. The three different stimuli differed from the target either on only one, or on all three features (eyes, nose, mouth). Reaction times varied considerably across the individual different responses in both conditions. In the first condition field differences consistently favoured the right field; in the second, two favoured the left and the third the right. In both conditions same responses were faster than at least one different response class. Several interpretations in terms of the distinction between "analytic" and "holistic" processes were entertained. Such processes themselves remain somewhat obscure, but there is nothing in the data to suggest that the two cerebral hemispheres might not be essentially ambivalent in their predilections for the two kinds of processing. In which case future research might profitably focus on the emerging plurality of experimental factors governing this cognitive ambivalence, rather than on the simple physical dichotomy.