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Publication Date:
01/03/1994
on Brain and cognition
by Trojano L, Grossi D
DOI: 10.1006/brcg.1994.1012
A critical, clinical review of single-case reports and group studies on visual mental imagery deficits is offered. Neuropsychological findings demonstrate that mental imagery relies upon dissociable processes which are localized in left-hemisphere posterior areas. Imagery defects thus may often be associated with visual recognition and naming impairments. On the other hand, the right hemisphere seems to play an analogous role in imagery and perception. Current theoretical models of imagery do not appear fully capable of accounting for available clinical data.
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Publication Date:
01/03/1993
on Cortex; a journal devoted to the study of the nervous system and behavior
by Chiacchio L, Grossi D, Stanzione M, Trojano L
We report an Italian patient affected by slowly progressive aphasia (SPA) lasting since four years when he first came to our observation. During the successive four years, we documented a progressive language decline resembling transcortical sensory aphasia, associated with a reading disorder corresponding to surface dyslexia, a form extremely rare in patients with native transparent language. His performance at standard intelligence tasks remained in the normal range, without any variation. CT scan showed left temporal atrophy. We emphasize the heterogeneity of the syndrome of SPA and suggest that it can represent one of the pictures of focal cortical degenerative disease, with variable onset, progression, and evolution.
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Publication Date:
01/02/1993
on Psychological medicine
by Grossi D, Becker JT, Smith C, Trojano L
Immediate memory for visuospatial information was assessed in patients affected by Alzheimer-type dementia but with unimpaired visuo-perceptual functions. Patients were given two tasks: one was a traditional visuospatial memory task (Corsi's block tapping test), the second explored specifically immediate memory for visuospatial patterns. The experiment was conducted in two parallel groups of patients in Italy and the United States, each with its own appropriate sample of normal control subjects. Results showed a specific deficit of visual working memory in demented patients, even in a task in which control subjects achieved error-free performance. These data are interpreted in the light of the Working Memory Model, and suggest that in dementia the functions of the Visuospatial Scratchpad, unlike the functions of the verbal subsystems, may be impaired.
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Publication Date:
01/01/1993
on Italian journal of neurological sciences
by Trojano L, De Cicco G, Grossi D
We aimed to ascertain whether non-apraxic, focal brain-damaged patients used abnormal constructional procedures. We tested a series of consecutive patients, classified according to lesion locus and side against a matched sample of normal volunteers. Subjects had to copy the Rey-Osterreith Figure, a complex and structured item that explores copying strategies. We used special testing and scoring methods to analyze different steps of the copy. Unlike the controls, the patients did not choose the central elements of the figure as guiding structures. All patient groups followed an equivalent "pathological", "piecemeal" procedure.
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Publication Date:
01/11/1992
on Brain and cognition
by Trojano L, Grossi D
A case is reported of an associative visual agnosic patient who could not draw from memory objects he could recognize, even though he could copy drawings flawlessly. His ability to generate mental visual images was found to be spared, as was his ability to operate upon mental images. These data suggest that the patient could generate mental images but could not draw from memory because he did not have access to stored knowledge about pictorial attributes of objects. A similar functional impairment can be found in some other visual agnosic patients and in patients affected by optic aphasia. The present case allows a discussion of relationships among drawing from memory, imagery, and copying procedures.
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Publication Date:
01/01/1992
on Brain and cognition
by Trojano L, Stanzione M, Grossi D
A patient is described with a rarely reported linguistic syndrome: he could repeat words but not nonwords. The patient produced semantic paraphasias in repetition and could read both words and nonwords flawlessly. His basic difficulties were localized in auditory phonological coding, identifying a clinical picture called "phonemic deafness." Short-term memory and verbal learning results suggested that a standard, selective short-term memory defect can be induced by auditory phonological coding deficits as well as by "pure" short-term memory capacity limitation and other phonological deficits. Findings also provided evidence that lexical-semantic code can allow normal verbal learning.
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Publication Date:
01/01/1991
on European neurology
by Grossi D, Trojano L, Chiacchio L, Soricelli A, Mansi L, Postiglione A, Salvatore M
This paper reports the clinical features of 2 patients affected by mixed transcortical aphasia. Both of them had extensive damage of the left hemisphere. Cerebral blood flow measurement showed a marked decrease in left-hemisphere flow. In particular, speech areas were found to be morphologically and functionally damaged. The present findings, together with a critical review of the literature, served as a starting point for a discussion of linguistic features, diagnostic criteria and classical neuroanatomical interpretation of mixed transcortical aphasia. The possible contribution of the right hemisphere in determining this aphasic syndrome is suggested.
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Publication Date:
01/10/1989
on Functional neurology
by Chiacchio L, Trojano L, Orsini A, Grossi D
Memory coding processes can be divided according to their attentional requirement into "automatic" and "effortful". The aim of current research was to explore both automatic and effortful processes in early and late stages of Alzheimer type dementia. Patients were classified on the basis of restrictive clinical and neuropsychological criteria, in order to pinpoint possible specific impairments in the two patients' subgroups. The present paper reports preliminary data about 15 mildly and 15 severely demented patients. Statistical analysis showed that both the automatic and the effortful coding processes are impaired at the late but also at the early stages of dementia.
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Publication Date:
01/05/1989
on Brain and cognition
by Grossi D, Modafferi A, Pelosi L, Trojano L
This paper develops the hypothesis of different roles of the two hemispheres in imaginal processes. A test designated the "o'Clock Test" is proposed, which contains closely confrontable perceptual and imaginal tasks. It enables examination of the abilities both to generate mental images and to explore them in their right and left halves (R + L Condition). This test was used to examine two patients, one severely affected by hemi-inattention resulting from a right posterior lesion, and the other with a selective deficit of imagery due to a left occipital lesion. The former demonstrated left neglect in both perceptive and imaginal capacities, while the latter was able to perform correctly only the perceptive tasks. These results suggest that the right hemisphere has functions of organization and spatial exploration at both perceptive and imaginal levels, and that the left hemisphere's role is to generate mental images.
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Publication Date:
01/09/1988
on Cortex; a journal devoted to the study of the nervous system and behavior
by Grossi D, Trojano L, Grasso A, Orsini A
An 18-year-old girl with a left parietal lesion caused by a closed-head injury exhibited a peculiar memory impairment. The patient showed selective "semantic amnesia" (severe loss of the stock of notions acquired prior to the disease), while autobiographic memory and spatial learning ability were preserved. The semantic/episodic distinction is discussed in the light of the patient's performance on neuropsychological tasks.