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S Cappa

Publications and source records attributed to S Cappa.

At least 19 recordsLinked to original sources
PubMed2005

REM sleep behaviour disorder.

REM sleep behaviour disorder (RBD) is a parasomnia characterised by nocturnal complex motor activity associated with dream mentation. RBD, which affects mainly older men, may be idiopathic or associated with other neurological disorders. A strong association between RBD and alpha-synucleinopathies has been recently observed, with the parasomnia often heralding the clinical onset of the neurodegenerative disease. The idiopathic form accounts for up to 60% of the cases reported in the three largest series of RBD patients. Follow-up studies in small samples revealed that a proportion of RBD patients will eventually develop Parkinson's disease and/or a dementia of Lewy bodies type in the years following the RBD diagnosis. Recently, neurophysiological and neuropsychological studies in idiopathic RBD have found evidence of central nervous system dysfunction. An impairment of cortical activity, specific neuropsychological deficits, signs of autonomic dysfunction and olfactory impairment have been observed in these patients, challenging the concept of idiopathic RBD. The detection of early markers of neurodegenerative disorders in idiopathic RBD, and the evaluation of their value by the combined application in prospective studies may be crucial for developing early intervention strategies.

Aggression↗
PubMed2004

Frontotemporal dementia: impact of P301L tau mutation on a healthy carrier.

Frontotemporal dementia (FTD) is the second commonest form of dementia after Alzheimer's disease, but its clinical and biological features are less well known. To uncover its earliest signs, we studied the main clinical, neuroimaging, and biochemical findings in an asymptomatic carrier from a three generation FTD family, bearing the P301L pathogenic mutation in the tau gene. Except for selective impairment on the Verbal Fluency Test for letters, all cognitive tests were normal. The brain computed tomography scan was normal, but the brain single photon emission computed tomography and statistical parametric mapping (SPECT-SPM) scan revealed bilateral frontal lobe hypoperfusion. Levels of total tau, 181P-tau, and Abeta1-42 in the cerebrospinal fluid were increased compared with control values. We conclude that detection of these distinctive abnormalities should improve early diagnostic accuracy for FTD and help distinguish it from Alzheimer's disease.

Adolescent↗
PubMed2003

Executive dysfunction and avoidant personality trait in myotonic dystrophy type 1 (DM-1) and in proximal myotonic myopathy (PROMM/DM-2).

A previous study in proximal myotonic myopathy (PROMM/DM-2) and myotonic dystrophy type 1 (DM-1) using brain positron emission tomography demonstrated a reduced cerebral blood flow in the frontal and temporal regions associated with cognitive impairment. The objective was to investigate further cognitive and behavioural aspects in a new series of patients with DM-1 and PROMM/DM-2. Nineteen patients with genetically determined PROMM/DM-2 and 21 patients with moderately severe DM-1 underwent neuropsychological testing and neuropsychiatric interviews. DM-1 and PROMM/DM-2 patients had significantly lower scores on tests of frontal lobe function compared to controls. Neuropsychiatric interviews demonstrated an avoidant trait personality disorder in both patient groups. Brain single photon emission computed tomography showed frontal and parieto-occipital hypoperfusion. The results suggest that there is a specific cognitive and behavioural profile in PROMM/DM-2 and in DM-1, and that this profile is associated with hypoperfusion in frontal and parieto-occipital regions of the brain.

Adult↗
PubMed2001

The integration of parallel and serial processing mechanisms in visual search: evidence from eye movement recording.

We examined timing and scanning paths of eye movements during a visual search task, in which subjects had to detect, as quickly as possible, the presence or absence of a target among distractors [Q-like element among O stimuli (QvsO) and vice-versa (OvsQ)]. According to an influential theory [Treisman, A. & Gelade, G. (1980) Cognitive Psychol, 12, 97--136; Treisman, A. & Sato, S. (1990) J. Exp. Psychol. Hum. Percept. Perform., 16, 459--478], only tasks yielding nonflat search functions (OvsQ) involve focal attention. Alternative models propose that all kinds of visual search are resolved by a biased competitive process, working in parallel across the visual field. Data show that QvsO and OvsQ tasks are characterized by quantitative rather than by qualitative differences in search strategy. No differences between the two tasks were found regarding either the percentage of saccades foveating single stimulus items or the timing of the button response with respect to the onset of the last foveation saccade within a trial. Furthermore, the number of saccades made during search predicted very accurately the time required to accomplish the task and fixation times were independent of the number of stimulus items. On the basis of our results there is no reason to postulate the occurrence of shifts of visuospatial attention, other than those associated with the executions of saccadic eye movements, which are driven by a parallel feature analysis of the visual scene, in both types of search tasks. A time-limited competitive model for attentive target identification, in which both parallel (competitive) and serial (attentive) processing mechanisms are integrated, can account for these findings, providing a unified conceptual framework for all kinds of visual search.

Adult↗
PubMed2000

[Approach to the patient in vegetative state. Part I: diagnosis].

Coma is the condition in which both components of consciousness, wakefulness and awareness, are lost. Therefore, the comatose patient neither opens the eyes, nor utters comprehensible words or follows commands. In the vegetative state (VS), awareness (including all cognitive function and emotion) is lost, while the vegetative functions, including breathing and sleep-wake cycles (the wakefulness), persist. Usually VS follows a state of coma caused by traumatic or anoxic brain damage. Pathologic brain examination demonstrates extensive subcortical, white matter, bilateral thalamic, and brainstem lesions in various combinations. Bilateral cerebral cortical lesions are rare, and therefore cortex can be "out of action" despite unaltered structure. More rarely, VS is caused by brain developmental malformations in children, or metabolic or degenerative diseases in children and adults. These are the only cases in which patients are not comatose before VS becomes apparent. After 6-8 weeks of coma, patients regain the eye opening. In such a condition, the term coma is no longer appropriate. If awareness is absent, the patient can be defined as in VS. Finally, the VS is defined as persistent (PVS) when it has continued for at least 1 month. The diagnosis of VS and PVS are clinical and require assessment over an adequate period of time and the skills of a multidisciplinary experienced team. Diagnosis is very complex in infants younger than 3 months, and is not applicable to preterm neonates, with the unique exception of infants with anencephaly. Among ancillary diagnostic tools, dynamic PET studies show promise.

Adult↗
PubMed1999

Reduced cerebral blood flow and impaired visual-spatial function in proximal myotonic myopathy.

OBJECTIVE: To compare brain involvement in myotonic dystrophy (DM) with that of proximal myotonic myopathy (PROMM). BACKGROUND: PROMM is a multisystem disease with many features in common with DM. METHODS: Twenty patients with DM (CTGF[500-700), 20 patients with PROMM, and 20 normal control subjects were studied. Neuropsychological testing was performed in 12 patients with PROMM and in 18 patients with DM; brain MRI was performed in 17 of 20 PROMM patients and 15 of 20 DM patients. Ten patients with PROMM and 11 patients with DM were subjected to H2(15)O PET. RESULTS: Two-thirds of the patients with PROMM and one-half of those with DM were impaired on visual-spatial recall, whereas one-third of the patients with PROMM and less than half of those with DM showed an impairment in visual-spatial construction. Brain MRI was normal, or showed only nonspecific white matter abnormalities in both PROMM and DM patients. PET studies in PROMM patients showed a bilateral decrease in regional cerebral blood flow (rCBF) of the orbitofrontal and medial frontal cortex, whereas DM patients had more widespread hypoperfusion that extended to the dorsolateral frontal cortex and subcortical regions. CONCLUSIONS: Impaired visual-spatial function may be present in proximal myotonic myopathy. This correlates best with a reduction in regional cerebral blood flow observed in H2(15)O PET brain scans rather than with specific structural abnormalities observed on brain MRI.

Adolescent↗
PubMed1998

Distinct brain loci in deductive versus probabilistic reasoning.

Deductive versus probabilistic inferences are distinguished by normative theories, but it is unknown whether these two forms of reasoning engage similar cerebral loci. To clarify the matter, positron emission tomography was applied during deductive versus probabilistic reasoning tasks, using identical stimuli. Compared to a language comprehension task involving the same stimuli, both probabilistic and deductive reasoning increased regional cerebral blood flow (rCBF) bilaterally in the mesial frontal region and in the cerebellum. In the direct comparison, probabilistic reasoning increased rCBF in left dorsolateral frontal regions, whereas deductive reasoning enhanced rCBF in associative occipital and parietal regions, with a right hemispheric prevalence. The results suggest that reasoning about syllogisms engages distinct brain mechanisms, depending on the intention to evaluate them deductively versus probabilistically.

Adult↗
PubMed1992

Oxiracetam in dementia: a double-blind, placebo-controlled study.

A multicentre, double-blind, between-patient study was carried out to evaluate the efficacy and tolerability of oxiracetam (800 mg tablet), in comparison with placebo, each given twice daily for 12 weeks to patients suffering from primary degenerative, multi-infarct or mixed dementia. Efficacy was assessed by a neuropsychological battery (simple reaction time, controlled associations, short story, Raven's Progressive Matrices, token test, digit span, word list learning), administered at the beginning and at the end of the study, and by a quality of life scale, administered at entry and after 6 and 12 weeks treatment. Sixty-five patients (28 men, 37 women, mean age 71 yrs) were enrolled; 58 completed the study: 2 on oxiracetam were withdrawn because of poor tolerability, 2 (one in each group) were withdrawn for poor compliance, one (on oxiracetam) for the occurrence of a transient ischaemic attack (defined as not related to the treatment) and 2 for administrative reasons. A significantly (p < 0.01) different effect in favour of oxiracetam was observed on the quality of life scale, and confirmed by significant (defined according to the Bonferroni technique) differences in some neuropsychological tests (e.g. controlled associations, short story). Four patients in the oxiracetam group complained of a total of 5 unwanted effects, and 1 on placebo complained of 3 unwanted effects, but none of them was withdrawn from the study.

Aged↗
PubMed1991

Sneddon syndrome: cerebral perfusion studies by Tc99m HM-PAO and SPECT.

Sneddon syndrome is a non-inflammatory, non-atherosclerotic disease involving small and medium-sized arteries of the brain and of the skin. The arteriographic examination is often negative despite progressive impairment of the neurological status. In 3 patients with Sneddon syndrome cerebral perfusion was assessed with single photon emission computerized tomography (SPECT) and technetium99 m-hexamethylpropylenamineoxime (Tc99 HM PAO). A correlation between clinical and SPECT finding was found, with significant focal reduction of regional cerebral blood flow (rCBF) in the two more severely affected patients.

Adult↗
PubMed1990

Topographic disorientation--a case report.

Topographical disorientation can be dissociated in two levels, agnosic and amnesic. A case of topographical disorientation due to a glioma of the splenium of corpus callosum illustrates the dissociation between the topographical memory impairment and the normal performances on the perceptual topographic tests.

Aged↗
PubMed1990

Temporary remission of left hemianesthesia after vestibular stimulation. A sensory neglect phenomenon.

In three right-brain damaged patients with contralesional neglect vestibular stimulation induced a temporary remission of left hemianesthesia, in addition to the well-known transient recovery of extrapersonal and personal neglect. These findings indicate that in neglect patients attentional factors may play an important role in producing apparently "primary" sensory deficits, which may be interpreted in terms of defective access to conscious processing.

Aged↗
PubMed1990

Insomnia and perceptual disturbances during flunarizine treatment.

We report two cases of sleep disturbances and perceptual disorder appearing in close temporal relationship with initiation of flunarizine therapy for migraine prophylaxis: these side effects disappeared after therapy interruption; resumption of the drug in one case was associated with symptom recurrence.

Female↗
PubMed1989

Visual neglect for far and near extra-personal space in humans.

The possible dissociation of unilateral neglect in far and near extra-personal space was systematically investigated using a modified version of the Wundt-Jastrow area illusion test. This task, which requires no motor response, has been shown to be sensitive to unilateral neglect. Stimuli were presented at two different distances (near and far) to a group of 70 patients with right hemispheric lesion (18 in acute and 52 in chronic stage). Twenty-eight patients evidenced unilateral neglect; that is, they displayed unexpected (i.e., contrary to the known illusory effect) responses when the stimuli were perceived as oriented toward the left side. However, performances in the two conditions were highly correlated and there were no individual instances of dissociation. These results suggest that the presence of a motor response may be necessary to show behavioral dissociations between different parts of extra-personal space.

Adult↗
PubMed1988

Crossed aphasia: functional studies with single photon emission computerized tomography.

The correlation between clinical picture, CT scan and regional cerebral blood flow (rCBF) assessed by single photon emission computerized tomography (SPECT) was investigated in two patients with crossed aphasia. The presence and degree or right hemisphere dysfunction, beyond the areas affected by CT, closely paralleled the time course of language disturbances in both patients: transient aphasia in case 1 was associated with temporary reduction of perfusion in the right hemisphere, while in case 2 persistent aphasia and apraxia were found along with severe right hemisphere hypoperfusion three year after the onset of stroke.

Aged↗
PubMed1988

Technetium-99m HM-PAO-SPECT study of regional cerebral perfusion in early Alzheimer's disease.

Regional cerebral perfusion was evaluated by single photon emission computed tomography (SPECT) using technetium-99m hexamethylpropyleneamine oxime ([99mTc]HM-PAO) in sixteen patients with Alzheimer's disease (AD) in early clinical phase and in 16 healthy elderly controls. In all patients transmission computed tomography (TCT) and/or magnetic resonance imaging (MRI) did not show focal brain abnormalities. Relative to normal subjects, AD patients showed significant reductions in cortical/cerebellar activity ratio: cortical perfusion was globally depressed with the largest reductions in frontal and posterior temporo-parietal cortices. Asymmetries of relative perfusion between cerebral hemispheres were also demonstrated when language was affected or visuospatial functions were unevenly impaired. In patients with early AD, SPECT provides functional information to be compared with clinical and psychometric data.

Aged↗
PubMed1987

Remission of hemineglect and anosognosia during vestibular stimulation.

The effects of vestibular stimulation on extrapersonal and personal neglect and on awareness of disease were investigated in four patients with severe neglect and anosognosia. Neglect phenomena improved in all patients, while an effect on anosognosia was found in two cases. These preliminary findings indicate a possible role of vestibular stimulation on hemispheric activation.

Aged↗