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Claudio Luzzatti

Department of Psychology, University of Milan-Bicocca
claudio.luzzatti@unimib.it

Journal articles

2012
Davide Crepaldi, Wei-Chun Che, I-Fan Su, Claudio Luzzatti (2012)  Lexical-semantic variables affecting picture and word naming in Chinese: a mixed logit model study in aphasia.   Behav Neurol 25: 3. 165-184  
Abstract: Lexical-semantic variables (such as word frequency, imageability and age of acquisition) have been studied extensively in neuropsychology to address the structure of the word production system. The evidence available on this issue is still rather controversial, mainly because of the very complex interrelations between lexical-semantic variables. Moreover, it is not clear whether the results obtained in Indo-European languages also hold in languages with a completely different structure and script, such as Chinese. The objective of the present study is to investigate this specific issue by studying the effect of word frequency, imageability, age of acquisition, visual complexity of the stimuli, grammatical class and morphological structure in word and picture naming in Chinese. The effect of these variables on naming and reading accuracy of healthy and brain-damaged individuals is evaluated using mixed-effect models, a statistical technique that allows to model both fixed and random effects; this feature substantially enhances the statistical power of the technique, so that several variables - and their complex interrelations - can be handled effectively in a unique analysis. We found that grammatical class interacts consistently across tasks with morphological structure: all participants, both healthy and brain-damaged, found simple nouns significantly easier to read and name than complex nouns, whereas simple and complex verbs were of comparable difficulty. We also found that imageability was a strong predictor in picture naming, but not in word naming, whereas the contrary held true for age of acquisition. These results are taken to indicate the existence of a morphological level of processing in the Chinese word production system, and that reading aloud may occur along a non-semantic route (either lexical or sub-lexical) in this language.
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Marco Marelli, Silvia Aggujaro, Franco Molteni, Claudio Luzzatti (2012)  The multiple-lemma representation of Italian compound nouns: a single case study of deep dyslexia.   Neuropsychologia 50: 5. 852-861 Apr  
Abstract: It is not clear how compound words are represented within the influential framework of the lemma-lexeme theory. Theoretically, compounds could be structured through a multiple lemma architecture, in which the lemma nodes of both the compound and its constituents are involved in lexical processing. If this were the case, syntactic properties of both the compound and its constituents should play a role when performing tasks involving compound processing, e.g., compound-word reading. This issue is investigated in the present study through an assessment of the performance of a deep dyslexic patient (GR) in three compound-reading experiments. In the first experiment, verb-noun (VN) compound nouns (e.g., lavapiatti, "dishwasher", lit. wash-dishes) were employed as stimuli, while in the second, VN compound stimuli were embedded in sentences, and were compared to paired verb phrases (e.g., lui lava piatti, "he washes dishes"). Position-specific effects were ruled out by means of a third experiment, which investigated the retrieval of noun-noun compounds (e.g., pescespada, "swordfish", lit. fishsword). In experiment 1, GR made errors on the verb constituent more frequently than on the noun, an effect that did not emerge in Experiment 2: when embedded in sentences, VN compounds were read significantly better than verb-phrases and no grammatical-class effect emerged. In Experiment 3, the first and the second constituent were read with the same level of accuracy. The disproportionate impairment, which emerged in reading the verb component of nominal VN compounds, indicates that the grammatical properties of constituents are being retrieved, and thus confirms access to the constituent lemma-nodes. However, the results suggested a whole-word representation when compounds are embedded in sentences; since the sentence context affects the access to compounds through syntactic constraints, whole-word representation is arguably at the lemma level as well (multiple-lemma representation). Experiment 3 indicates that these effects cannot be accounted for by a position-specific impairment.
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Carlo Abbate, Pietro Davide Trimarchi, Gian Pietro Salvi, Anna Maria Quarenghi, Carlo Vergani, Claudio Luzzatti (2012)  Delusion of inanimate doubles: Description of a case of focal retrograde amnesia.   Neurocase Jan  
Abstract: This paper reports the case of a patient, M.P., who developed delusion of inanimate doubles, without Capgras syndrome, after traumatic brain injury. His delusional symptoms were studied longitudinally and the cognitive impairments associated with delusion were investigated. Data suggest that M.P. did 'perceive' the actual differences between doubles and originals rather than 'confabulate' them. The cognitive profile, characterized by retrograde episodic amnesia, but neither object processing impairment nor confabulations, supports this hypothesis. The study examines the nature of object misidentification based on Ellis' and Staton's account and proposes a new account based on concurrent unbiased retrieval of semantic memory traces and biased recollection of episodic memory traces.
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Marco Marelli, Silvia Aggujaro, Franco Molteni, Claudio Luzzatti (2012)  Understanding the mental lexicon through neglect dyslexia: a study on compound noun reading.   Neurocase Apr  
Abstract: The present study employs neglect dyslexia (ND) as an experimental model to study compound-word processing; in particular, it investigates whether compound constituents are hierarchically organized at mental level and addresses the possibility of whole-word representation. Seven Italian-speaking patients suffering from ND participated in a word naming task. Both left-headed (pescespada, swordfish) and right-headed (astronave, spaceship) Italian compound nouns were used as stimuli. Non-existent compounds, which were generated by substituting the leftmost constituent of a compound with an orthographically similar word (e.g., *pestespada, *plaguesword), were also employed. A significant headedness effect emerged in the group analysis: patients read left-headed compounds better than right-headed compounds. A significant lexicality effect was also found: the participants read real compounds better than their non-existent compound pairs. Moreover, logit mixed-effects analyses indicated a left-hand constituent frequency effect. Results are discussed in terms of hierarchical representation of compounds and direct access to compound lemma nodes.
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2011
Davide Crepaldi, Manuela Berlingeri, Eraldo Paulesu, Claudio Luzzatti (2011)  A place for nouns and a place for verbs? A critical review of neurocognitive data on grammatical-class effects.   Brain Lang 116: 1. 33-49 Jan  
Abstract: It is generally held that noun processing is specifically sub-served by temporal areas, while the neural underpinnings of verb processing are located in the frontal lobe. However, this view is now challenged by a significant body of evidence accumulated over the years. Moreover, the results obtained so far on the neural implementation of noun and verb processing appear to be quite inconsistent. The present review briefly describes and critically re-considers the anatomo-correlative, neuroimaging, MEG, TMS and cortical stimulation studies on nouns and verbs with the aim of assessing the consistency of their results, particularly within techniques. The paper also addresses the question as to whether the inconsistency of the data could be due to the variety of the tasks used. However, it emerged that neither the different investigation techniques used nor the different cognitive tasks employed fully explain the variability of the data. In the final section we thus suggest that the main reason for the emergence of inconsistent data in this field is that the cerebral circuits underlying noun and verb processing are not spatially segregated, at least for the spatial resolution currently used in most neuroimaging studies.
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A Basso, S Cattaneo, L Girelli, C Luzzatti, A Miozzo, L Modena, A Monti (2011)  Treatment efficacy of language and calculation disorders and speech apraxia: a review of the literature.   Eur J Phys Rehabil Med 47: 1. 101-121 Mar  
Abstract: The aim of the study was to evaluate the efficacy of the treatment for language and calculation disorders and for speech apraxia in vascular subjects. Only therapeutic methods that could be qualified as neuropsychological were taken into account. For language disorders, we searched the pertinent literature published from 1950 to August 31, 2007 by means of electronic data banks and we took into consideration the Cochrane review, and papers in Cicerone et al. and Cappa et al. systematic reviews. For acalculia we examined the literature from 1980 by carrying out research on electronic data banks; for speech apraxia, studies emerged from a search of PUBMED. Aphasia therapy has been clearly demonstrated efficacious in groups of subjects if sufficiently prolonged/intensive. Treatment for specific disorders (words and sentences processing, reading, writing) studied in series of single patients, though always efficacious, reaches a lower level of recommendation due to the lack of RCT. Only a few studies tackled the problem of efficacy in case of speech apraxia and calculation disorders. Results are positive but data are scanty. Efficacy of aphasia therapy seems well established in group of subjects and well-promising for speech apraxia and calculation disorders. It is suggested, however, that the term "aphasia" covers widely different impairments and that RCT are not the best instrument to evaluate efficacy; the importance of chronicity is underlined.
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Pietro Davide Trimarchi, Claudio Luzzatti (2011)  Implicit chord processing and motor representation in pianists.   Psychol Res 75: 2. 122-128 Mar  
Abstract: The aim of this paper is to assess the relevance of pitch dimension in auditory-motor interaction. Several behavioural and brain imaging studies have shown that auditory processing of sounds can activate motor representations, an effect which is however elicited only by action-related sounds, i.e., sounds linked to a specific motor repertoire. Music provides an appropriate framework for further exploration of this issue. Three groups of participants (pianists, non-pianist musicians and non-musicians) were tested with a shape decision task where left-hand and right-hand responses were required; each visual stimulus was paired with an auditory task-irrelevant stimulus (high-pitched or low-pitched piano-timbre chords). Of the three groups, only pianists had longer reaction times for left-hand/high-pitched chords and right-hand/low-pitched chords associations. These findings are consistent with an auditory-motor effect elicited by pitch dimension, as only pianists show an interaction between motor responses and implicit pitch processing. This interaction is consistent with the canonical mapping of hand gestures and pitch dimension on the piano keyboard. The results are discussed within the ideo-motor theoretical framework offered by the Theory of Event Coding (Hommel et al. in Behav Brain Sci 24:849-937, 2001).
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2010
Paola Angelelli, Alessandra Notarnicola, Anna Judica, Pierluigi Zoccolotti, Claudio Luzzatti (2010)  Spelling impairments in Italian dyslexic children: phenomenological changes in primary school.   Cortex 46: 10. 1299-1311 Nov/Dec  
Abstract: Although spelling difficulties are constantly associated with developmental dyslexia, they have been largely neglected by the majority of studies in this area. This study analyzes spelling impairments in developmental dyslexia across school grades in Italian, a language with high grapheme-to-phoneme correspondence.
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2009
Marcella Laiacona, Erminio Capitani, Giusy Zonca, Ilaria Scola, Paola Saletta, Claudio Luzzatti (2009)  Integration of lexical and sublexical processing in the spelling of regular words: a multiple single-case study in Italian dysgraphic patients.   Cortex 45: 7. 804-815 Jul/Aug  
Abstract: In this study we investigated 12 cases of "mixed dysgraphia", a spelling impairment where regular words are spelt better than either ambiguous words or regular non-words. Two explanations of mixed dysgraphia were formerly offered by Luzzatti et al. (1998): (i) a double functional lesion of the orthographic output lexicon (or damage to its access) and of the acoustic-to-phonological conversion; and (ii) some kind of interaction/summation between lexical and sublexical spelling routes when processing regular words. We first analysed whether a double functional lesion was sufficient to explain the mixed dysgraphia, checking acoustic-to-phonological conversion by means of the repetition of words and non-words: the answer was positive in five cases and uncertain in three. We tested the remaining four cases to see if there was an interaction between lexical and sublexical processing of regular words, quantifying for each patient, on a probabilistic basis, the separate contribution of the residual lexical and sublexical resources. We investigated whether the processing along these routes was simultaneous but independent ("independent cooperation") or if instead there was "interaction", i.e., the simultaneous activity led to an added increase of efficiency over and above the mere combination of separate success probabilities. For one case the processing along the two routes was independent, in the other three cases an interaction resulted. Following the same approach, we found that for the five cases with a double functional lesion, the observed success on regular word spelling was higher than that expected on a probabilistic basis, but the interpretation of this finding was different.
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Nicolò F Bernardi, Silvia Aggujaro, Marco Caimmi, Franco Molteni, Angelo Maravita, Claudio Luzzatti (2009)  A new approach to rhythm cueing of cognitive functions: the case of ideomotor apraxia.   Ann N Y Acad Sci 1169: 417-421 Jul  
Abstract: Although positive effects of rhythm cueing on motor control in neurologic disorders are known, no studies have yet focused on patients suffering from impaired programming of complex actions. One patient suffering from ideomotor apraxia (a potentially ideal experimental paradigm to test the effect of rhythm on high-level motor control) underwent two rehabilitation training sets differing only for the presence or absence of rhythm cueing. Both sets of training increased the patient's proficiency, but rhythm cueing was significantly more effective, during the training as well as during the post-training uncued test. Ideomotor apraxia represents an effective model to test the effects of rhythm on high-level motor control.
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2008
Manuela Berlingeri, Davide Crepaldi, Rossella Roberti, Giuseppe Scialfa, Claudio Luzzatti, Eraldo Paulesu (2008)  Nouns and verbs in the brain: grammatical class and task specific effects as revealed by fMRI.   Cogn Neuropsychol 25: 4. 528-558 Jun  
Abstract: The wide variety of techniques and tasks used to study the neural correlates of noun and verb processing has resulted in a body of inconsistent evidence. We performed a functional magnetic resonance imaging (fMRI) experiment to detect grammatical class effects that generalize across tasks. A total of 12 participants undertook a grammatical-class switching task (GCST), in which they were presented with a noun (or a verb) and were asked to retrieve the corresponding verb (or noun), and a classical picture naming task (PNT) widely used in the previous aphasiological and imaging literature. The GCST was explicitly designed to ensure control over confounding variables, such as stimulus complexity or imageability. Conjunction analyses of the haemodynamic responses measured in the two tasks indicated a shared verb-related activation of a dorsal premotor and posterior parietal network, pointing to a strong relationship between verb representation and action-oriented (visuo-)spatial knowledge. On the other hand, no brain area was consistently associated with nouns in both tasks. Moreover, there were task-dependent differences between noun and verb retrieval both at behavioural and at physiological level; the grammatical class that elicited the longest reaction times in both tasks (i.e., verbs in the PNT and nouns in the GCST) triggered a greater activation of the left inferior frontal gyrus. Therefore, we suggest that this area reflects a general increase in task demand rather than verb processing per se.
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2006
Davide Crepaldi, Silvia Aggujaro, Lisa Saskia Arduino, Giusy Zonca, Graziella Ghirardi, Maria Grazia Inzaghi, Mariarosa Colombo, Gennaro Chierchia, Claudio Luzzatti (2006)  Noun-verb dissociation in aphasia: the role of imageability and functional locus of the lesion.   Neuropsychologia 44: 1. 73-89  
Abstract: 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].
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Alessio Toraldo, Claudio Luzzatti (2006)  Which variability?   Brain Lang 96: 2. 154-6; discussion 157-70 Feb  
Abstract: 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.
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Claudio Luzzatti, Silvia Aggujaro, Davide Crepaldi (2006)  Verb-noun double dissociation in aphasia: theoretical and neuroanatomical foundations.   Cortex 42: 6. 875-883 Aug  
Abstract: 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.
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2005
Sara Mondini, Claudio Luzzatti, Paola Saletta, Nadia Allamano, Carlo Semenza (2005)  Mental representation of prepositional compounds: evidence from Italian agrammatic patients.   Brain Lang 94: 2. 178-187 Aug  
Abstract: 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.
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2004
Thomas Benke, Claudio Luzzatti, Giuseppe Vallar (2004)  Hermann Zingerle's "Impaired perception of the own body due to organic brain disorders". 1913. An introductory comment, and an abridged translation.   Cortex 40: 2. 265-274 Apr  
Abstract: 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.
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Paola Angelelli, Anna Judica, Donatella Spinelli, Pierluigi Zoccolotti, Claudio Luzzatti (2004)  Characteristics of writing disorders in Italian dyslexic children.   Cogn Behav Neurol 17: 1. 18-31 Mar  
Abstract: This study characterizes the spelling impairment of Italian dyslexic children and evaluates the relationship between reading and spelling disorders.
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Sara Mondini, Claudio Luzzatti, Giusy Zonca, Caterina Pistarini, Carlo Semenza (2004)  The mental representation of verb-noun compounds in Italian: evidence from a multiple single-case study in aphasia.   Brain Lang 90: 1-3. 470-477 Jul/Sep  
Abstract: 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.
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2003
Claudio Luzzatti, Marcella Laiacona, Daniela Agazzi (2003)  Multiple patterns of writing disorders in dementia of the Alzheimer type and their evolution.   Neuropsychologia 41: 7. 759-772  
Abstract: 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.
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2002
Claudio Luzzatti (2002)  Johann August Philipp Gesner (1738-1801). A review of his essay "The language amnesia" in the bicentennial anniversary of his death.   J Hist Neurosci 11: 1. 29-34 Mar  
Abstract: 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.
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Maria Teresa Guasti, Claudio Luzzatti (2002)  Syntactic breakdown and recovery of clausal structure in agrammatism.   Brain Cogn 48: 2-3. 385-391 Mar/Apr  
Abstract: 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.
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Claudio Luzzatti, Rossella Raggi, Giusy Zonca, Caterina Pistarini, Antonella Contardi, Gian-Domenico Pinna (2002)  Verb-noun double dissociation in aphasic lexical impairments: the role of word frequency and imageability.   Brain Lang 81: 1-3. 432-444 Apr/Jun  
Abstract: 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.
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Sara Mondini, Gonia Jarema, Claudio Luzzatti, Cristina Burani, Carlo Semenza (2002)  Why is "Red Cross" different from "Yellow Cross"?: a neuropsychological study of noun-adjective agreement within Italian compounds.   Brain Lang 81: 1-3. 621-634 Apr/Jun  
Abstract: 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.
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2001
M Laiacona, C Luzzatti, G Zonca, C Guarnaschelli, E Capitani (2001)  Lexical and semantic factors influencing picture naming in aphasia.   Brain Cogn 46: 1-2. 184-187 Jun/Jul  
Abstract: Picture naming requires early visual analysis, accessing stored structural knowledge, semantic activation, and lexical retrieval. We tested the effect of perceptual, lexical, and semantic variables on the performance of aphasics in picture naming and assessed prevalence of natural categories vs artifact dissociations. Forty-nine aphasics were asked to name 60 pictures, from three natural (animals, fruits, and vegetables) and three artificial categories (tools, furniture, and vehicles). For each item visual (drawing complexity, image agreement), semantic (prototypicality, concept familiarity) and lexical variables (word frequency, name agreement) were available. The effect of these variables showed individual differences; altogether, visual complexity had little influence, whereas lexical and semantic variables were more influential. Name agreement was most important, followed by word frequency. On a multiple single case analysis 10 patients (20%) showed a natural/artificial category dissociation. Five of the six subjects faring better with artifacts were males, and all of four patients faring better with natural categories were females. Interpretations of this finding are discussed.
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C Luzzatti, H Whitaker (2001)  Jean-Baptiste Bouillaud, Claude-François Lallemand, and the role of the frontal lobe: location and mislocation of language in the early 19th century.   Arch Neurol 58: 7. 1157-1162 Jul  
Abstract: In 1825, Jean-Baptiste Bouillaud read a paper at the Royal Academy of Medicine in Paris supporting Franz Gall's theory of a relation between speech and the frontal lobes. Bouillaud argued that if the frontal lobes are crucial to speech, 2 conditions must be satisfied: when the frontal lobes are affected, speech must also be affected; conversely, when the frontal lobes are spared, speech is also spared. Following these principles, he tested and argued in support of Gall's theory by analyzing the data from 2 neuropathological casebooks (Lallemand, 1820-1823; Rostan, 1820 and 1823). We now know that Bouillaud was wrong, since the crucial dichotomy is between the left and right hemispheres and not between the anterior and posterior areas. What is interesting is that the actual data refute Bouillaud's conclusion. We replicated his experiment by reanalyzing the 147 clinical cases described by Lallemand. There were, of course, some cases with frontal lesions and speech disorders; other cases, however, had speech disorders with lesions outside the frontal lobes, and still others had frontal lesions without speech disorders. Although Bouillaud did not notice it, as we expected, almost all patients with speech disorders had a left hemisphere lesion.
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C Luzzatti, S Mondini, C Semenza (2001)  Lexical representation and processing of morphologically complex words: evidence from the reading performance of an Italian agrammatic patient.   Brain Lang 79: 3. 345-359 Dec  
Abstract: The study of patients with acquired language disorders has provided crucial evidence for contemporary theories on mental lexical representation. This is particularly true for the representation of morphologically complex words. In this paper we analyzed the performance of a patient (M.B.) affected by agrammatism and dyslexia. M.B. was required to read aloud simple and morphologically complex words. The patient's pattern of errors was interpreted as the result of a predominant use of the lexical routine (phonological dyslexia). Three reading tasks were developed which allowed us to test M.B.'s ability to read morphologically complex words (reading of regular and irregular plurals; reading of high- and low-frequency singular and plural nouns; reading of evaluative suffixes). Errors were determined by frequency effect rather than by type of suffix (i.e., inflectional or derivational). High-frequency morphologically complex items seemed to meet stored representations, thus avoiding the parsing procedures that are required for less frequent items. These results are in keeping with dual route models of lexical representation of morphologically complex words.
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2000
C Luzzatti, A Toraldo, G Ghirardi, L Lorenzi, C Guarnaschelli (2000)  Syntactic comprehension deficits in agrammatism.   Brain Cogn 43: 1-3. 319-324 Jun/Aug  
Abstract: Eleven agrammatic and 16 fluent aphasic patients were given a comprehension task consisting of simple, active and passive reversible sentences. The purpose of the study is to reconsider the comprehension disorders in agrammatism, and particularly of passive reversible sentences, to test to what extent Grodzinsky's trace deletion hypothesis (TDH) is generalizable to other types of NP-movement, and finally to ascertain whether the pattern of impairment observed in agrammatism differs from that of fluent aphasic patients. The study confirms that trace analysis may be selectively impaired in agrammatism. However, this deficit is not the only mechanism underlying comprehension disorders and cannot be said to occur in all agrammatic patients. Comprehension disorders also involve the processing of clitic object pronouns which also underly NP-movement. Finally, the impairment found in fluent aphasic patients differs, both in type and severity, from that of agrammatic patients, thus confirming the peculiar aspects of the agrammatic comprehension deficit suggested by Grodzinsky's TDH.
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1999
H I Kushner, C Luzzatti, S Finger (1999)  A perplexing document in the early history of Gilles de la Tourette Syndrome: Melotti's rendition of a "Lecture of Charcot" (including a complete translation from the Italian with commentary).   J Hist Neurosci 8: 1. 5-20 Apr  
Abstract: In 1885, Dr. Guilio Melotti published an Italian translation of a lecture on "Convulsive Tics with Coprolalia and Echolalia" given by Jean-Martin Charcot. Although this lecture often has been cited as an authoritative statement of Charcot's view, until now it has not been translated into English. The lecture presents a number of statements that appear nowhere else in Charcot's published corpus, including some that seem to contradict Charcot's other pronouncements on maladie des tics. Although the Melotti-Charcot lecture may portray Charcot's position accurately in many passages, the article most likely is a compilation from a variety of sources.
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1998
C Luzzatti, T Vecchi, D Agazzi, M Cesa-Bianchi, C Vergani (1998)  A neurological dissociation between preserved visual and impaired spatial processing in mental imagery.   Cortex 34: 3. 461-469 Jun  
Abstract: Studies on primates have shown that visual and spatial perceptual analysis depends on two separate neural pathways, associated with the processing of "what" and "where" an object is (visual characteristics and spatial coordinates, respectively). Similar dichotomies have been proposed by cognitive psychologists (e.g., the contrast between visual and spatial processing in working memory) and by neuropsychologists (e.g., the distinction between topographic agnosia and amnesia). In this paper we report the case of a patient with a severe spatial disorientation whose perceptual processing of visual and spatial information was normal, but in imagery tasks she had a dissociation between preserved visual and impaired spatial processing. While her ability to represent objects visually was intact, she failed in any task requiring mental rotation, recall of spatial position or execution of spatially based imagery operations. The case clearly demonstrates that visual and spatial imagery are functionally independent processes which must rely on different underlying neural systems. This pattern of impairment also explains the associated topographical amnesia as an inability to integrate spatial information in a mental map.
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C Luzzatti, M Laiacona, N Allamano, A De Tanti, M G Inzaghi (1998)  Writing disorders in Italian aphasic patients. A multiple single-case study of dysgraphia in a language with shallow orthography.   Brain 121 ( Pt 9): 1721-1734 Sep  
Abstract: We report results of a writing task given to 53 mildly to moderately aphasic Italian subjects. The task was designed to test the writing performance along the subword-level routine for the spelling of regular words and non-words, and along the lexical routine for the spelling of irregular words. The aim of the study was to identify the incidence of different dysgraphic subtypes in Italian, a language that is considered to have shallow orthography. Its spelling, however, is not completely free of ambiguity. A five-part writing task was used: (i) words with regular one-sound-to-one-grapheme conversion; (ii) words with regular syllabic conversion; (iii) words with ambiguous transcription; (iv) loan-words; and (v) non-words. For regular words, the effects of word length and word frequency, and of the variables determining the complexity of the acoustic-to-phonological conversion (continuant versus plosive phones; consonant-vowel sequence versus doubled consonants or consonant clusters) were also considered. Patients' performances were classified according to the presence of a dissociation between (i) regular words and non-words, (ii) regular words and words with unpredictable spellings, and (iii) one-to-one and syllabic conversions. The 53 aphasic patients span the whole spectrum of dysgraphic taxonomy. Thirty-nine patients, in particular, manifested a dissociated pattern of performance. Eighteen patients showed a prevalent surface dysgraphic pattern and seven a phonological one, while 11 patients showed a mixed pattern (i.e. a better performance for regular words than for ambiguous words or regular non-words). Three patients showed a specific deficit for regular syllabic conversion rules only. A high rate of 'mixed dysgraphia' suggests either a mutual interaction of the two impaired routines when regular words are written, or two separate functional lesions: one at the level of the auditory-to-phonological conversion procedure, the other at the level of the orthographic output lexicon.
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1997
A Bazzini, F Pezzoni, G Zonca, C Guarnaschelli, F Zelaschi, C Luzzatti (1997)  [The evaluation of aphasic deficits for the definition of a targetted logotherapeutic treatment].   G Ital Med Lav Ergon 19: 2. 29-35 Apr/Jun  
Abstract: The Aachener Aphasie Test (AAT) is the major German test for the diagnosis of aphasic disorders. The test is easy to use and is valid and reliable for the diagnosis of aphasia and its severity and to evaluate the recovery of the aphasic disorder after language rehabilitation. The AAT is, however, not sufficient to define cognitively sound logotherapeutic treatment. The use of tasks which are based on cognitive functional models allows the identification of specific processing levels that have been damaged by a cerebral lesion, and the definition of a focussed rehabilitation plan. In this paper, we will discuss the results of a cognitive neurolinguistic treatment in a patient who suffered of Broca's aphasia with agrammatism and phonological dyslexia.
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1996
C Luzzatti, R De Bleser (1996)  Morphological processing in Italian agrammatic speakers: eight experiments in lexical morphology.   Brain Lang 54: 1. 26-74 Jul  
Abstract: Agrammatic speech production has often been characterized as amorphology. This study of two Italian agrammatic patients shows that, with respect to inflectional morphology of simple and derived nouns, the morphological features of gender and number are almost fully preserved for one patient (MG) and only mildly disturbed in the other patient (DR). Like inflection, the use of derivational suffixation as a means of word-building is only mildly disturbed in both patients. However, they show a severe disturbance with respect to inflectional morphology of lexical compounds, which requires syntactic analysis at the word level. Moreover, they are severely impaired in the choice of the function word for the construction of prepositional compounds, syntactically generated phrases which have the status of a word. Apart from such syntax-dependent morphological and word-building operations, neither inflectional nor derivational morphology are seriously disturbed in our patients. The apparent amorphology in their spontaneous speech can thus not be explained by a disorder of morphological representations in the lexicon system perse. In another study (De Bleser and Luzzatti, 1994) we were able to show that the patients had severe problems with the implementation of morphology in specific syntactic contexts, thus pointing to a problem in morphosyntactic rather than morpholexical processing as a factor contributing to agrammatic speech production.
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1994
R De Bleser, C Luzzatti (1994)  Morphological processing in Italian agrammatic speakers syntactic implementation of inflectional morphology.   Brain Lang 46: 1. 21-40 Jan  
Abstract: Most current linguistic and psycholinguistic characterizations of agrammatic production start from the observation that in spontaneous speech inflectional suffixes are either dropped or substituted by default forms, depending on the morphological structure of the language. So far, little experimental evidence has entered theory construction. In this paper, elicited data of two Italian patients with agrammatic speech are presented. The tasks involved the production of a past participle suffix in different sentence contexts. In Italian, the past participle has to agree in gender and number with the grammatical features of an antecedent noun, pronoun, or empty element. It is shown that both patients mastered the general principles of the agreement rule, and that they could produce correct inflectional suffixes in several tasks. Furthermore, the point of breakdown in their performance was syntactic rather than morphological, namely, when there were no overt morphological cues for the identification of the thematic roles in the sentence. These data cannot be accounted for by theories formulated in terms of the syntactic or postsyntactic deletion of suffixes or the functional elements underlying their realization. At least for the patients in this study, morphological substitutions arose as a result of an impairment in the syntactic processing of content words rather than functors.
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K Schonauer, C Luzzatti, G Denes (1994)  [Physiology, psychology and pathology of writing and spelling--an overview].   Fortschr Neurol Psychiatr 62: 8. 271-279 Aug  
Abstract: Writing and spelling are conceived as concerted actions comprising cognitive planning, motor action and an expressive content. In literate societies the individual use of alphabetic systems is acquired immediately after speech as a "cultural technique". As such these systems demand specific cognitive and motor skills which have been analysed primarily on the basis of neurological and psychiatric syndromes. We distinguish primary developmental disturbances and secondarily acquired disturbances of writing and spelling, categorizing the latter into four essential disturbance areas: linguistic command, motor execution, automatism control and dynamic tonus regulation. The clinical significance of writing and spelling is not confined to its possible disturbances. In pathologically induced restrictions of cognitive functions or of social skills the fact is rather that the written language frequently contributes to the development of individual coping strategies. From the psychodynamic aspect, written communication is characterized principally by its proximity-regulating function.
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C Luzzatti, J Davidoff (1994)  Impaired retrieval of object-colour knowledge with preserved colour naming.   Neuropsychologia 32: 8. 933-950 Aug  
Abstract: Two cases (G.G. and A.V.) are described of cognitive impairment resulting from herpes simplex infection. Both cases demonstrated anomic disorders and impairments in drawing but only in G.G.'s drawings was there a reliable selective impairment for items from natural categories. Both cases, however, showed an impairment for the retrieval of knowledge concerning the colours of objects. The impairment has, in the past, been ascribed to interference from colour anomia; this was not so for the present cases. For G.G. and A.V., impairments in object-colour retrieval were related to errors in picture naming. More errors were associated with items that induced circumlocutions than to those that were correctly named. The impairment was also present for some items that were named correctly. The patients' impairments are discussed within a model in which object-colour knowledge is functionally situated between an object's shape description and its output phonology but on a separate route from other associated object knowledge.
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1993
L Lonzi, C Luzzatti (1993)  Relevance of adverb distribution for the analysis of sentence representation in agrammatic patients.   Brain Lang 45: 3. 306-317 Oct  
Abstract: In this study, it is shown that functional categories are present in agrammatic grammar. Specifically, the verb-adverb order is investigated in three agrammatic patients by means of a constituent ordering task. It is shown that when the verb is in a nonfinite form, it either precedes or follows the specifier-like adverb (both positions are correct), but when the verb is finite, the adverb always follows it (which is the only possible order). The conclusions are that (i) a functional category (namely Inflection), which is responsible for the relative order verb-adverb (of the relevant class), must exist in agrammatic grammar, and (ii) agrammatic aphasia cannot be described as a syntactic impairment involving basic sentence structure.
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1991
L Bandera, S Della Sala, M Laiacona, C Luzzatti, H Spinnler (1991)  Generative associative naming in dementia of Alzheimer's type.   Neuropsychologia 29: 4. 291-304  
Abstract: Forty-eight patients with mild to moderate dementia of Alzheimer's type (DAT) were tested with a generative associative naming task, a task that combines the aspects of fluency and of word association tests. The variables taken into consideration were the number of adequate and inadequate responses, conventionality, word frequency and lexical-semantic relation to the target. DAT patients' performances were compared to those of a group of control subjects matched for sex, age and educational level. As a group, the patients gave fewer adequate responses, more idiosyncratic responses and perseverations, while there was no difference in the qualitative variables. However, the analyses of the performance profiles suggest that, irrespective of the severity of the disease, two major subgroups of DAT patients may be identified: (1) a first subgroup of subjects produced words with a lower conventionality rate and these were mostly in propositional relationship to the target; they also produced a higher rate of idiosyncratic responses and perseverations. (2) A second subgroup of subjects gave more conventional responses, mostly in the hierarchical-categorical relationship. The disorders of the former subgroup seem to correspond to a disrupted access to some relatively spared semantic abilities, whereas those of the latter to a semantic breakdown.
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C Luzzatti, K Poeck (1991)  An early description of slowly progressive aphasia.   Arch Neurol 48: 2. 228-229 Feb  
Abstract: Slowly progressive aphasia without generalized dementia has become an important issue of present-day neuropsychological research. Historically, credit for the first description is usually given to Pick. Another German-speaking author who has published a vivid description of a pertinent cases is Pick's contemporary, Max Rosenfeld. This author has also observed a patient with slowly progressive spatial disorientation and visual recognition deficit, and he has discussed these patients in a remarkably modern way in the context of partial atrophy of the brain.
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1988
K Poeck, C Luzzatti (1988)  Slowly progressive aphasia in three patients. The problem of accompanying neuropsychological deficit.   Brain 111 ( Pt 1): 151-168 Feb  
Abstract: Three patients are described presenting with a slowly progressive aphasic disorder associated with degenerative cortical disease. The symptoms began in the presenium and the length of illness was 4 to 5 years. The language disorder corresponded in all patients to a severe form of amnesic aphasia but a moderate to marked semantic breakdown was also found. Formal language examination was complemented by extensive neuropsychological testing. This revealed a severe deficit in language-dependent cognitive tasks. The patients were given a follow-up language and neuropsychological examination. In addition to the deterioration of language functions, a significant decline was observed in nonverbal intelligence tasks even though their level of performance still remained within the normal range. Follow-up with standardized intelligence tests might detect a trend towards generalized dementia in similar cases. This would mean that these patients should be considered as presenting with slowly progressive aphasia preceding generalized dementia.
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1985
A Basso, E Capitani, C Luzzatti, H Spinnler, M E Zanobio (1985)  Different basic components in the performance of Broca's and Wernicke's aphasics on the Colour-Figure Matching Test.   Neuropsychologia 23: 1. 51-59  
Abstract: It is known that focal damage of the left hemisphere causes poor performances in a number of tasks devoid of overt verbal connotation, often referred to as "non-verbal intelligence", "association" or "abstract attitude" tasks. However, it is not clear whether the existence of a unitary basic functional defect to account for the faulty performances outlined above can be supposed. In this investigation we have compared the behaviour of left-hemisphere damaged patients grouped according to aphasia type and have studied the extent to which two different, widely used tests of this supposed "non-verbal basic ability" (i.e. the Weigl Sorting Test and the Raven Progressive Matrices) overlap in their predictive power of the performance of a non-verbal association task, i.e. the Colour-Figure Matching Test. Notwithstanding the identical level of performance in the three tests between groups having different aphasia types, a clear-cut dissociation was found between Broca's and Wernicke's aphasics; in the former group the Colour-Figure Matching Test was highly correlated only with Weigl Sorting Test and in the latter only with Progressive Matrices. The conclusions are that in this case the breakdown of non-verbal basic resources does not coincide in patients with different types of aphasia, and the hypothesis of the existence of a unitary basic defect caused by left hemisphere damage is not in line with our findings.
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1981
A Basso, E Capitani, C Luzzatti, H Spinnler (1981)  Intelligence and left hemisphere disease. The role of aphasia, apraxia and size of lesion.   Brain 104: Pt 4. 721-734 Dec  
Abstract: The Raven Progressive Matrices and four subtests of the Wechsler-Bellevue Performance Scale were given to 173 left hemisphere patients subdivided according to presence/absence, type (fluent/non-fluent) and severity (moderate/severe) of aphasia. Constructive and ideomotor apraxia scores and CT scan data of each subject entered the statistical analysis. Factors significant in producing a low score on Progressive Matrices and Wechsler-Bellevue were presence of aphasia and constructive apraxia. Site and size of lesion per se failed to account for the intelligence scores. The relationship between aphasia, apraxia, intelligence test scores, and CT scan data were discussed in an attempt to clarify the meaning of these low intelligence test scores in aphasics and to assess the underlying roles of the brain lesions in this deficit. It appears that there are a number of methodological difficulties complicating interpretation of the intellectual deficit based on the Progressive Matrices and Wechsler-Bellevue scores, since performance on these tests is adversely affected by both aphasia and apraxia.
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1980
A Basso, C Luzzatti, H Spinnler (1980)  Is ideomotor apraxia the outcome of damage to well-defined regions of the left hemisphere? Neuropsychological study of CAT correlation.   J Neurol Neurosurg Psychiatry 43: 2. 118-126 Feb  
Abstract: A CAT scan was recorded from 123 patients with left hemisphere damage from stroke. They were divided into four groups according to presence or absence of ideomotor apraxia and length of illness (15 to 90 days and over 90 days). The lesions were mapped and compared in the four experimental groups for anteroposterior dimension, lesion depth--deep-seated lesions deing separated from lesions with a superficial component--and position with respect to the Sylvian fissure for lesions encroaching on the surface. In the anteroposterior dimension there is no material difference in the distribution of the lesions with respect to length of illness. Moreover, any difference is hardly detectable between the profiles for patients with and without ideomotor apraxia except for the higher frequency of deep lesions in the non-apraxic group. The same holds true for "small" lesions.
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A Basso, E Capitani, M Laiacona, C Luzzatti (1980)  Factors influencing type and severity of aphasia.   Cortex 16: 4. 631-636 Dec  
Abstract: The influence of etiology and sex on aphasia type and the relation of age to the severity and type of language disorders have been assessed in 718 right-handed aphasic patients. Both trauma and neoplasia are associated with fluent aphasia significantly more often, while sex proved to have no influence on aphasia type. The frequency distribution of age according to type and severity of aphasia - studied in vascular patients only (N = 566) - demonstrated that fluency and severity are significantly associated with older age.
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1979
E Bisiach, C Luzzatti, D Perani (1979)  Unilateral neglect, representational schema and consciousness.   Brain 102: 3. 609-618 Sep  
Abstract: Right brain-damaged patients with unilateral neglect were asked to detect differences within pairs of patterns moving left- or rightward behind a narrow vertical slit. It was seen that differences occurring on the left side of the mentally reconstructed images were less easily detected; therefore it is suggested that a representational disorder plays a primary role in unilateral neglect. In the light of these findings, it is possible to take into consideration some implications of unilateral neglect for theories of conscious brain activity.
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C Luzzatti, G Scotti, A Gattoni (1979)  Further suggestions for cerebral CT-localization.   Cortex 15: 3. 483-490 Sep  
Abstract: A method of obtaining lateral diagrams of brain lesions or structures from CT-scan pictures has been described and tested for accuracy with satisfactory results. Possible sources of error are discussed.
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1978
E Bisiach, C Luzzatti (1978)  Unilateral neglect of representational space.   Cortex 14: 1. 129-133 Mar  
Abstract: Two patients showing left unilateral neglect were asked to describe imagined perspectives of familiar surroundings. Left-sided details were largely omitted in the descriptions. Some theoretical implications of the occurrence of unilateral neglect in representational space are briefly considered.
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1976
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