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Claudio Luzzatti

Publications and source records attributed to Claudio Luzzatti.

13 recordsLinked to original sources
PubMed2006

Noun-verb dissociation in aphasia: the role of imageability and functional locus of the lesion.

Aphasic patients occasionally manifest a dissociated naming ability between objects and actions: this phenomenon has been interpreted as evidence of a separate organization for nouns and verbs in the mental lexicon. Nevertheless Bird et al. [Bird, H., Howard, D., Franklin, S. (2000). Why is a verb like an inanimate object? Grammatical category and semantic category deficits. BrainandLanguage, 72, 246-309], suggested that the damage underlying noun-verb dissociation affects the corresponding semantic concepts and not the lexical representation of words; moreover, they claimed that many dissociations reported in literature are caused merely by a strong imageability effect. In fact, most authors used a picture-naming task to assess patients' naming ability, and due to the fact that this test involves the use of pictures to represent actions and objects, nouns were frequently more imageable than verbs [Luzzatti, C., & Chierchia, G. (2002). On the nature of selective deficit involving nouns and verbs. RivistadiLinguistica, 14, 43-71]. In order to overcome this drawback, we devised a new task - nouns and verbs retrieval in a sentence context (NVR-SC) - in which nouns and verbs have the same imageability rate. Patients' performance on this task is compared with that obtained by the same patients on a standard picture-naming task. Of the 16 aphasic patients with a selective verb deficit, as revealed by the picture-naming task, two continued to show dissociation in the NVR-SC task, while 14 did not. The data indicate that at least some patients have an imageability-independent lexical deficit for verbs. The functional locus/i of the damage is also considered, with particular reference to the lemma/lexeme dichotomy suggested by Levelt et al. [Levelt, W. J. M., Roelofs, A., & Meyer, A. S. (1999). A theory of lexical access in speech production. BehavioralandBrainSciences, 22, 1-75].

Analysis of Variance↗
PubMed2006

Verb-noun double dissociation in aphasia: theoretical and neuroanatomical foundations.

This paper reports the results of several studies on the mechanisms underlying Verb-Noun (V-N) dissociation. The objectives of the studies were to ascertain the location of the lesions causing predominant V or N impairment and to shed light on the different mental representations of these word classes through analyses of the data from neuropsychological patients. With regard to lesion sites, results obtained through an anatomo-correlative study on 15 V-impaired and 5 N-impaired aphasic patients indicate that lesions causing predominant N impairment were mostly located in the middle and inferior left temporal area. Three alternative lesion sites were associated with a V deficit (left posterior temporo-parietal lesions; large left fronto-temporal perisylvian lesions; deep lesions of the insula and/or the basal ganglia). In contrast to the results obtained from several neuropsychological and neuroimaging studies, none of the V-impaired patients had an isolated frontal lesion. The second aim is to discuss grammatical class interaction with semantic factors such as actionality or imageability (said to be the real cause of V-N dissociation). The retrieval of Ns and Vs in a sentence context was tested on 16 V-impaired aphasic patients and the resulting data indicate that imageability interacts with the retrieval of Ns and Vs, but cannot completely account for their dissociation.

Anomia↗
PubMed2005

Which variability?

Drai and Grodzinsky provide a valuable analysis that offers a way of disentangling the effects of Movement and Mood in agrammatic comprehension. However, their mathematical implementation (Beta model) hides theoretically relevant information, i.e., qualitative heterogeneities of performance within the patient sample. This heterogeneity is crucial in the variability debate.

Aphasia, Broca↗
PubMed2005

Mental representation of prepositional compounds: evidence from Italian agrammatic patients.

The processing of Prepositional compounds (typical Neo-latin noun--noun modifications where a head noun is modified by a prepositional phrase, e.g., mulino a vento, windmill) was preliminarily studied with a group of six agrammatic aphasic patients, and, in more detail, with a further agrammatic patient (MB). Omission was the most frequent error type in naming, whereas in the other tasks (repetition, reading, writing, and completion) errors were mostly substitutions of the target preposition. This happened even with fully lexicalized compound forms, i.e., those forms where the linking preposition is syntactically and semantically opaque. These findings are interpreted in terms of a dual-route theory of lexical access to morphologically complex words.

Adolescent↗
PubMed2004

Hermann Zingerle's "Impaired perception of the own body due to organic brain disorders". 1913. An introductory comment, and an abridged translation.

In the late 1970's Edoardo Bisiach and his coworkers provided definitive evidence that spatial unilateral neglect involves a disorder of the internal representation of extra-personal space. A few years later Bisiach and Berti (1987) revived the so far neglected contribution of an Austrian neurologist, Hermann Zingerle (1913). Ninety years ago Zingerle had described the symptom-complex of two right-brain-damaged patients, who showed left hemisomatoagnosia, unawareness of left hemiplegia, and left motor neglect. In addition to the detailed case reports, Zingerle had put forward a unitary interpretation of these deficits in terms of a disordered representation of one side of the body (dyschiria). A unitary representational account of these unilateral impairments was conspicuously absent in the contemporary neurological literature (Anton, Pick, Babinski), and attracted Bisiach's interest. An abridged translation of Zingerle's paper is provided. The clinical case reports and Zingerle's conclusions are discussed, with reference both to Bisiach's views, and to present knowledge of unilateral spatial neglect.

Body Image↗
PubMed2004

Characteristics of writing disorders in Italian dyslexic children.

OBJECTIVE: This study characterizes the spelling impairment of Italian dyslexic children and evaluates the relationship between reading and spelling disorders. BACKGROUND: Developmental spelling deficits are much less investigated than reading deficits. Based on the dual-model approach, studies of English-speaking subjects describe a surface and a phonological dysgraphia. In languages with shallow orthographies, there is evidence of surface and phonological dyslexia, but no data are available for dysgraphia. METHODS: Eighteen dyslexic children were studied. Writing was investigated by means of a spelling test that included regular words with one-sound-to-one-letter correspondence, regular words requiring syllabic conversion rules, words with unpredictable transcription, and nonwords with one-sound-to-one-letter correspondence. The dyslexics' spelling errors were compared with those of 30 age-matched proficient readers. RESULTS: The dyslexic participants were very slow readers. Their errors were compatible with the hypothesis of a prevalent use of the sublexical reading procedure (i.e., surface dyslexia). They were also generally impaired with respect to the control children in all subsections of the spelling test. However, multivariate and single case analyses as well as qualitative analysis of errors indicated that their major problem was writing words with unpredictable transcription. This failure was consistent with the view of prevalent subword level processing in writing. CONCLUSION: The pattern of the spelling impairment mirrors the children's reading impairment, with most children suffering from surface dysgraphia.

Adolescent↗
PubMed2003

Multiple patterns of writing disorders in dementia of the Alzheimer type and their evolution.

This paper reports the results obtained from a writing task given to 23 Italian patients suffering from mild to moderate dementia of the Alzheimer's type (DAT). Spelling performance was tested with a task that taps the sub-word-level (spelling of regular words and nonwords), and the lexical route (spelling of regular and irregular words), in line with contemporary models of writing. Each patient's performance was classified according to the emergence of dissociated patterns of damage between regular words and nonwords and between regular and irregular words. The 23 DAT patients span the whole spectrum of dysgraphic taxonomy; five showed the characteristic pattern of impairment of surface dysgraphia, two showed the characteristics of phonological dysgraphia, while a mixed pattern (i.e. better performance on regular words compared to irregular words and regular nonwords) emerged in seven cases. Three patients presented undifferentiated writing disorders, two were completely agraphic, while four patients showed only minimal or no writing defects. The rate of dissociated impairments in the lexical and the sub-word-level routine is very similar to that observed after acute focal brain damage, which contradicts the hypothesis that degenerative brain damage selectively impairs writing performance along the lexical-semantic route. To test the hypothesis that surface sub-word-level processing abilities are affected only during the evolution of the disease, nine patients were tested longitudinally after an interval of 6-12 months. Once again, the data showed high variability across subjects, and do not seem to support involvement of the sub-word-level spelling routine only at a late stage in the development of the disease.

Aged↗
PubMed2002

Johann August Philipp Gesner (1738-1801). A review of his essay "The language amnesia" in the bicentennial anniversary of his death.

On the 200th anniversary of Johann August Philipp Gesner's death, this paper summarizes and discusses a paper on language amnesia published in 1770. The author had clear knowledge of selective mental impairments resulting from brain diseases, and of separate mental representations for words and their underlying concepts. However, to explain the language impairment, Gesner suggested that it would not be caused by focal damage to a specific anatomic and functional unit of the mind, but is the consequence of a general sluggishness of the mental processes.

Aphasia↗
PubMedDate not supplied

Verb-noun double dissociation in aphasic lexical impairments: the role of word frequency and imageability.

Neurolinguistic studies have provided important evidence regarding the organization of lexical representations and the structure of underlying conceptual knowledge; in particular, it has been shown that the retrieval of verbs and nouns can be damaged selectively. Dissociated lexical damage is proof of an independent mental organization of lexical representations and/or of the underlying processes. The aim of the present study is to estimate the rate of dissociated impairments for nouns and verbs on a large sample of mild to moderate aphasic patients and to investigate the mechanisms underlying such phenomena. In addition, the authors wished to verify to what degree the impairment for nouns and verbs is related to a specific type of language disorder. A confrontation naming task for verbs and nouns was administered to 58 aphasic patients. The major lexical (word frequency and age of acquisition) and semantic variables (familiarity and imageability of the underlying concept) were considered for each noun and verb used in the task. Verbs were distinguished by major functional classes (transitive, intransitive, and ergative verbs). The data collected from this task were analyzed twice: (i) as a group study comparison of major aphasic subgroups and (ii) as a multiple single case study to evaluate the differences on the naming of verbs and nouns and the effect of the lexical semantic variables on each individual patient. The results confirm the existence of dissociated naming impairments of verbs and nouns. Selective impairment of verbs is more frequent (34%) than that of nouns (10%). In many cases, the dissociated pattern of naming impairment disappeared when the effect of the concomitant variables (word frequency and imageability) was removed, but in approximately one-fifth of the cases the noun or verb superiority was preserved. Noun superiority emerged in five of six agrammatic patients. Both the naming of verbs (n = 9) or of nouns (n = 6) could be impaired selectively in fluent aphasic patients. The results lend support to the hypothesis of an independent mental organization of nouns and verbs, but a substantial effect of imageability and word frequency suggests an interaction of the naming impairment with underlying lexical and semantic aspects.

Aphasia, Wernicke↗
PubMedDate not supplied

Why is "Red Cross" different from "Yellow Cross"?: a neuropsychological study of noun-adjective agreement within Italian compounds.

This study investigates the performance of two Italian nonfluent aphasic patients on noun-adjective agreement in compounds and in noun phrases. A completion, a reading, and a repetition task were administered. Results show that both patients were able to correctly inflect adjectives within compounds, but not in noun phrases. Moreover, they were sensitive to constituent order (noun-adjective vs adjective-noun) within noun phrases, but less so within compounds. These results suggest differential processing for compounds as compared to noun phrases: While the latter require standard morphosyntactic operations that are often impaired in aphasic patients, the former can be accessed as whole words at the lexical level.

Adult↗
PubMedDate not supplied

The mental representation of verb-noun compounds in Italian: evidence from a multiple single-case study in aphasia.

This study seeks information on the mental representation of Verb-Noun (VN) nominal compounds through neuropsychological methods. The lexical retrieval of compound nouns is tested in 30 aphasic patients using a visual confrontation naming task. The target names are VN compounds, Noun-Noun (NN) compounds, and long morphologically simple nouns (LSN). In order to check the ability to produce simple nouns and verbs in the same participants, a further visual confrontation naming task of objects and actions is used. Results of the study confirm that several patients with disproportionate verb deficit are also impaired in naming VN compounds. Data are in favor of a (de)compositional processing of compound words. A further group of patients is selectively more impaired with compound nouns than with comparably long simple nouns, irrespective of their VN or NN morphological structure. It is suggested that this impairment is to be ascribed to a specific disorder in retrieving two different lexemes with a single lexical entry.

Adolescent↗
PubMedDate not supplied

Syntactic breakdown and recovery of clausal structure in agrammatism.

We studied the recovery of clause structures in four agrammatic patients by performing a longitudinal analysis of their spontaneous production. We classified their utterances in terms of legitimacy of the syntactic structure and rate of subordination. The results show that, initially, patients omit verbs, avoid subordination, just employ present tense, and substitute finite verbs with infinitives. During the recovery they start employing other tenses and subordinate clauses and reduce the use of infinitives. Data suggest a mixed syntactic and morphological origin of the impairment. Assuming that phrasal representations are built bottom-up from an array of lexical items, we propose that syntactic structures recover stepwise, with the lower portion of the syntactic tree becoming accessible before higher portions. We claim that, despite superficial similarities between agrammatic and children's speech, e.g., use of infinitives instead of finite verbs, a unified account is not viable.

Adolescent↗