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C Caltagirone

Publications and source records attributed to C Caltagirone.

At least 19 recordsLinked to original sources
PubMed1992

Lateralization of the epileptogenic focus by computerized EEG study and neuropsychological evaluation.

The localization of the epileptogenic focus relies on different factors. In patients with partial seizures, asymmetries in EEG background activity were measured by a statistical evaluation of spectral data. Neurophysiological results were compared with neuropsychological findings and MRI. Fifteen of 22 patients showed asymmetries in EEG background activity. The most prominent abnormality was a statistically significant increase of slow activity observed in 59% of cases. Delta asymmetry coincided with the site of lesions, evidenced by MRI, in 83% of patients; with the site of decreased beta activity in 60% and with the maximum level of spiking activity in 58% of cases. Neuropsychological tests showed a lateralization of the hemispheric function which coincided with delta asymmetry in 33% of patients. These results suggest that the EEG background activity, when compared with other parameters, may represent a useful method in lateralizing the epileptogenic focus.

Adolescent↗
PubMed1979

Semantic disorders of auditory language comprehension in right brain-damaged patients.

A test of auditory language comprehension was given to 110 right brain-damaged patients and to 94 normal controls in order to check if patients with lesions of the right (nondominant) hemisphere make a significantly higher number of semantic errors than normals. Confirmation of the hypothesis was obtained, but the relationship between semantic errors and lesion of the right hemisphere did not seem a simple and direct one. In fact, most of the lexical-semantic errors were due to associated variables (such as unilateral spatial agnosia and general mental deterioration) and not to the lesion of the right hemisphere per se. These data do not suggest a specific semantic capacity of the nondominant hemisphere but rather stress the fragility of the lexical-semantic organization at the cortical level.

Brain Damage, Chronic↗
PubMed1979

Foveal versus peripheral retinal responses: a new analysis for early diagnosis of multiple sclerosis.

Visual potentials evoked by brief flashes (VEPs) were recorded in 85 patients with MS, 30 healthy controls and 25 neurological patients without demyelinating diseases. In a group of 44 patients, diffuse field stimulation was used, resutling in 15 altered responses (34%). In a second group of 41 patients with superimposable characteristics including age, sex, diagnosis of MS (definite, probable and possible) and score on the Rose's scale, the separate responses of central and peripheral retina were analysed. A total of 30 abnormal VEPs were recognized (73%) with the following distribution: 16 foveal VEPs (78%), 4 peripheral responses (13%) and 26 centreperiphery latency differences (CPLD, 60%). Twenty subjects of Group A with normal or slightly altered full field VEPs were retested with both stimulating methods with the following result: 3 altered full field VEPs (15%) and 15 abnormal CPLD (75%). With diffuse field stimulation, the correlation between the VEP scores and the results of other examinations (visual, pyramidal, etc.) were insignficant; on the contrary, the CPLD was clearly correlated with the involvement of the visual and other systems in the fluctuating clinical course of MS.

Adolescent↗
PubMed1979

Validity of some neuropsychological tests in the assessment of mental deterioration.

Eighty-three control subjects and 200 patients suspected of diffuse cerebral damage were submitted to the Mental Deterioration Battery. Three independent judges evaluated each patient on the basis of all available data. Only 103 patients, unanimously classed as demented by the three judges were retained. On the basis of controls' performances, the scores obtained by each demented patient in the various tests were corrected for age and educational level. Both single tests and the Battery as a whole discriminated normal controls from demented patients at a very satisfactory level.

Age Factors↗
PubMed1979

Jakob-Creutzfeldt disease: analysis of EEG and evoked potentials under basal conditions and neuroactive drugs.

EEG and evoked potential (EP) recordings of a female (aged 70) affected with Jakob-Creutzfeldt disease (JCD) are reported. A comparison of neurophysiological tests under basal conditions and pharmacological stimulation with methylphenidate, diazepam and piracetam was performed. Diazepam and methylphenidate produced a flattening of triphasic complexes and changes in background activity; piracetam did not seem to influence the abnormal brain bioelectrical environment. The authors conclude that EEG and EP abnormalities in JCD can be ascribed to two separate and interacting sources: (1) exaggerated massive excitatory input coming from a deep thalamic pace-maker throughout the diffuse projecting system, and (2) lack of inhibitory intracortical mechanisms.

Aged↗
PubMed1979

The relationships between conceptual and semantic-lexical disorders in aphasia.

A nonverbal test of conceptual thinking was administered to 55 normal controls and to 203 patients with monohemispheric brain lesions (74 aphasics and 129 nonaphasic brain-damaged patients), in order to study the relationships between conceptual impairment of aphasic patients and breakdown of the semantic-lexical level of integration of language. A very high number of aphasic patients (54 out of 74) and a limited number of nonaphasic brain-damaged subjects (31 out of 129) obtained a pathological score on the test of conceptual thinking, but only some components of the aphasic symptomatology seemed closely linked to the conceptual disorder. In fact a non-significant relationship was found between conceptual impairment and: ("fluent" or "non-fluent") clinical type of aphasia; severity of aphasic disturbance. On the contrary, a strong relationship was found between conceptual disorder and impairment of the semantic-lexical level of integration of language. These findings seem to show that conceptual disturbance and semantic-lexical troubles are closely linked in aphasia.

Aphasia↗
PubMed1977

Gangliosides in the treatment of mental deterioration. A double-blind comparison with placebo.

Thirty patients showing signs of mental deterioration were submitted to a neuropsychological battery before and after treatment with gangliosides. Their performances were compared, in a double-blind study, with those obtained on the same tests by 30 patients affected by similar degrees of dementia and treated with placebo. The improvement shown on Raven's Coloured Progressive Matrices and on Immediate Visual Memory by the active group was significantly higher than that shown by the placebo group. Furthermore, an evaluation of the overall effect of gangliosides therapy showed a highly significant difference between the active and placebo group, still in favour of the subjects treated with gangliosides. It is concluded that gangliosides may exert a positive effect in the treatment of demential syndromes.

Clinical Trials as Topic↗
PubMed1977

A neurolinguistic model for the study of aphasia.

After having briefly discussed some of the most important models that are now used to understand or to classify the aphasic troubles, the authors explain the neurolinguistic model they are actually using to study some aspects of aphasics' verbal and nonverbal behavior. This theoretical model distinguishes proper linguistic from extralinguistic disturbances in the various clinical forms of aphasia. The existence in aphasia of extralinguistic components that might, in some way, influence verbal performances, is accepted by most authors. Much less obvious is the existence, at least in some clinical forms of aphasia, of proper linguistic (competence) disturbances. Our theoretical model assumes that in most clinical forms of aphasia some impairment of the semantic (lexical) structures of language exists, and it maintains that this trouble can be found both at the expressive and at the receptive level, both in verbal and in nonverbal tasks. Th results of some experimental investigations which give some support to this theoretical model, are briefly discussed.

Aphasia↗
PubMed1977

Distinctive features of unilateral spatial agnosia in right and left brain-damaged patients.

In order to study the distinctive features of unilateral spatial agnosia shown by right and left brain-damaged patients, a test of copying drawings with guiding landmarks was given to 83 control subjects and to 248 patients affected by right (n = 108) or left (n = 140) hemispheric damage. The test enabled us to obtain a quantitative assessment both of the lines omitted ('omissions') and of the lines wrongly traced ('errors') on the half page contralateral to the damaged hemisphere. Results showed that contralaterally to the hemispheric locus of lesion a clear-cut double dissociation can be found between right and left brain-damaged patients: the former showed a striking tendency to omit the lines lying on the left half of the sheet, whereas the latter tended mainly to trace faulty lines on the right half of the drawings.

Agnosia↗
PubMed1976

[Digital agnosia and lesions of the parietal lobe].

130 patients with focal brain damage have been submitted to non-verbal finger identification tasks. The results of this research can be summarized as follows: -when bilateral finger agnosia is studied with non-verbal tasks, no difference can be shown between right and left parietal lesions; -in left brain damaged patients the bilateral form of finger agnosia is generally due to large lesions involving the parietal lobe; -in right brain damaged patients the unilateral form of finger agnosia is almost always due to lesions centered on the parietal region.

Agnosia↗
PubMed1975

Pattern of ipsilateral clinical extinction in brain-damaged patients.

A test of double tactile simultaneous stimulation was given to 212 patients affected by focal (178) or diffuse (34) cerebral lesions to study the order of dominance between face, hand, and foot. Both in focal and in diffuse brain-damaged patients, a striking dominance of the face over the hand and foot was found. No significant difference between hand and foot was seen, but a mild prevalence of the foot over the hand was suggested by a cumulative analysis of our results. These findings do not support the hypothesis of a continuous downward gradient of dominance from rostral to caudal regions of the body.

Brain Damage, Chronic↗
PubMed1975

[Acoustic and semantic disturbances of comprehension in aphasia].

The authors carried out a verbal auditory comprehension test on 115 aphasic patients, 44 patients suffering from a left hemispheric lesion without aphasia and 120 normal subjects used as acontrol group. The test also revealed either disorders in acoustico-phonemic discrimination or difficulities in semantic differentiation. The main aim of the research was to check experimentally the theory propounded by Alajouanine and colleagues (1964) according to which, in Wernicke's aphasia, it is possible to demonstrate a twofold correlation between disorders of comprehension and speech disorders both phonemic and semantic. Only one part of the theory of Alajouanine and colleagues has been confirmed by our experiments for our results have shown that there is a very close correlation between semantic paraphasias and disorders of semantic differentiation whilst no correlation can be found between phonemic paraphasias and disturbances in auditory phonemic discrimination.

Aphasia↗
PubMedDate not supplied

[An experimental study of autotopagnosia (author's transl)].

One hundred and twenty patients with unilateral cerebral hemisphere damage (54 aphasics, 21 non-aphasic left and 45 right brain-damaged patients and 57 control subjects without cerebral lesions were given a battery of verbal and non-verbal tests of autotopagnosia, with the aim of studying the relationships between disorders of body schema and the side of the hemispheric lesion. A second aspect of our research consisted in understanding whether impairment in naming and pointing to body parts following verbal commands was really a specific symptom or if the same difficulty was found when patients were asked to name or to point to parts of objects other than the human body. Our results have shown that: 1) the aphasic patients are significantly more impaired than the non-aphasic patients on all the tests, non-verbal as well as verbal; 2) when results obtained on tests of naming and of pointing to parts of the human body were matched with results obtained on tests of naming and of pointing to parts of objects other than the human body, no difference could be demonstrated. These findings suggest that autotopagnosia is a nonspecific symptom, and that it does not find a satisfactory explanation in terms of "disorders of the body schema".

Adult↗