PubMed Health⌕ Search

Biomedical subjects

G Bottini

Publications and source records attributed to G Bottini.

At least 19 recordsLinked to original sources

Italian neuropsychological instruments to assess memory, attention and frontal functions for developmental age.

In this study, a series of tests exploring long-term verbal memory (the Short Story Test), attention (a modified version of Attentional Matrices and the Trail Making Test) and frontal functions (a modified version of the Frontal Assessment Battery) have been standardised on an Italian population of 283 children aged 5-14. Raw scores for each test have been adjusted for a series of variables (child's age, years of parents' education, handedness, gender) and transformed in equivalent scores enabling direct comparison across measures. This study was promoted by LICE (the Italian League Against Epilepsy) in order to provide Italian instruments standardised on the developmental age population and to study some of the most frequently impaired cognitive functions in epilepsy.

Adolescent↗

Left caloric vestibular stimulation ameliorates right hemianesthesia.

BACKGROUND: Left caloric vestibular stimulation (CVS) transiently reduces impairments of right-brain-damaged patients with left unilateral neglect, including left hemianesthesia, contralateral to the side of the lesion (contralesional). Conversely, no effect on right contralesional hemianesthesia in left-brain-damaged patients is seen with right CVS. This discrepancy is unexplained. METHODS: The authors explored the effect of CVS on right- and left-brain-damaged patients with hemianesthesia. One left-brain-damaged patient had an fMRI study during tactile stimulation before and after left CVS. The same fMRI touch study, without CVS, was performed in neurologically unimpaired subjects. RESULTS: A transient remission of right hemianesthesia associated with left brain damage was observed, provided that cold CVS was administered to the left ear. In the left-brain-damaged patient studied with fMRI, left CVS modulated the neural response to right hand tactile stimuli of a portion of the secondary somatosensory area (SII) of the right hemisphere. In neurologically unimpaired subjects, fMRI scans showed that the same part of area SII in the right hemisphere was activated by ipsilateral right-sided touches and to a larger extent than area SII in the left hemisphere by left-sided touches. CONCLUSIONS: Left caloric vestibular stimulation is effective on both left and right hemianesthesia because it modulates the hemisphere that has a more complete representation of, or is capable to attend to, the whole somatosensory surface of the body. These results suggest a hardwired hemispheric asymmetry in hand representation, starting from a somatotopically organized brain region such as area SII.

Adult↗

Shared cortical anatomy for motor awareness and motor control.

In everyday life, the successful monitoring of behavior requires continuous updating of the effectiveness of motor acts; one crucial step is becoming aware of the movements one is performing. We studied the anatomical distribution of lesions in right-brain-damaged hemiplegic patients, who obstinately denied their motor impairment, claiming that they could move their paralyzed limbs. Denial was associated with lesions in areas related to the programming of motor acts, particularly Brodmann's premotor areas 6 and 44, motor area 4, and the somatosensory cortex. This association suggests that monitoring systems may be implemented within the same cortical network that is responsible for the primary function that has to be monitored.

Adult↗

An examination of self-reported chronic conditions and health status in the 2001 Medicare Health Outcomes Survey.

OBJECTIVES: To estimate the prevalence of chronic conditions in managed care-enrolled Medicare seniors (age 65 years plus) and to examine the association between self-reported chronic conditions and health status, as measured by the SF-36. METHODS: Data were obtained from the 2001 Medicare Health Outcomes Survey (HOS). The HOS is conducted to assess the quality of care provided to Medicare beneficiaries enrolled in managed care. The survey questionnaire, which was administered by phone or mail, includes the SF-36 and items addressing demographic characteristics, depressive symptoms, and chronic conditions. The SF-36 produces eight multi-item scale scores and physical and mental component summary scores. For this analysis, an ordinary least squares regression model was conducted using the SF-36 scales and summary scores as dependent variables to estimate the association between each chronic condition and the scale scores after adjusting for demographic variables. RESULTS: More than three-fourths of the respondents had at least one chronic condition. Among the conditions, hypertension (56.6%) arthritis of the hip or knee (39.7%) and arthritis of the hand or wrist (33.3%) were the most commonly reported. Compared with other variables, age and arthritis were most highly associated with the SF-36 measures reflective of physical health. Depressive symptoms had the strongest association with the SF-36 measures most reflective of mental health. Among the chronic conditions, the adverse impact of having difficulty in controlling urination, a relatively neglected condition, was only second to depressive symptoms in its negative relationship with vitality, social-functioning, and mental health. CONCLUSION: Chronic conditions were commonly reported among the older adults. The unique associations found between chronic conditions and domains of health status demonstrate the importance of examining the burden of these conditions in terms of functioning and well-being. The findings of this study may help inform decision making at the patient, health plan, and societal levels.

Adult↗

Preserved functional competence of perilesional areas in drug-resistant epilepsy with lesion in supplementary motor cortex: fMRI and neuropsychological observations.

We report a presurgical fMRI study and a longitudinal behavioral and structural MRI study in a 26-year-old right-handed woman with drug-resistant epilepsy of the supplementary motor region with cytoarchitectural dysplasia and minimal cortico-subcortical gliotic damage. fMRI scans were acquired during a silent phonemic verbal fluency task (VF), an automatic counting task (CT), and a finger-tapping motor task (MT). These were all compared with rest. Presurgical neuropsychological assessment was substantially normal with only a minor deficit in the domain of visuo-constructive and complex motor-planning skills. Noticeably, performance on phonemic verbal fluency was normal. Presurgical fMRI results revealed a normal specialization of left SMA and pre-SMA, including a fine-grained somatotopy for mouth and hand representations despite epilepsy. Immediately after surgical removal of the epileptogenic zone (the posterior third of the superior and middle frontal gyri including pre-SMA and part of SMA, and part of the anterior cingulate region--all of which were active presurgically at the fMRI tests), the patient suffered from transcortical motor aphasia temporarily. One year after surgery, she still showed impaired performance in the verbal fluency tasks while naming and comprehension were recovered. The patient was now free from seizures. This fMRI study supports the case that repeated seizures per se may not be sufficient to alter the distribution of neural representations of cognitive function. Selective behavioral impairment after surgical removal of brain areas that were activated during presurgical fMRI permits us to establish a causal link between these activations and task performance. This link could not have been made on the basis of activation patterns or lesion data taken on their own. These findings support the case that some epileptic patients may represent a unique opportunity for cognitive neuroscience studies.

Adult↗

The influence of contralesional targets on the cancellation of ipsilesional targets in unilateral neglect.

Neglect of contralesional stimuli and perseverative behavior on ipsilesional stimuli may co-occur on a target cancellation task. Our aim was to investigate whether the presence vs. absence of contralesional targets can modify perseveration on ipsilesional targets. We studied four right brain-damaged patients with left neglect and perseverative behavior on screening cancellation tasks. We compared their cancellation performance in two conditions: (i) targets equally distributed on both sides of space and (ii) targets confined to the right side. One patient showed no significant difference in perseveration between these two conditions; in contrast, three patients perseverated significantly more in condition (i) than in condition (ii). These results suggest that, at least in some patients, information from the 'neglected' targets is not completely lost, but rather it affects behavior in the ipsilesional side. The traditional dichotomy 'bad space-good space' would not apply here.

Aged↗

Cerebral representations for egocentric space: Functional-anatomical evidence from caloric vestibular stimulation and neck vibration.

The internal representation of space involves the integration of different sensory inputs-visual, somatosensory/proprioceptive, vestibular-yielding reference frames which are not based on individual peripheral sensory codes, being organized instead in ego-centred (e.g. head, trunk, arm) and object- or environment-centred coordinates. Lateralized or direction-specific stimulation of peripheral sensory systems, such as caloric vestibular stimulation (CVS), posterior neck muscle mechanical vibration (NV) and optokinetic stimulation, can induce a distortion of egocentric coordinates, causing, for example, a deviation of the subjective straight ahead in pointing tasks. Appropriate forms of this stimulation can also temporarily improve a variety of pathological manifestations of unilateral neglect. We used PET measurements of regional cerebral blood flow changes in normal volunteers to measure the brain responses shared by CVS and NV. We show that somatosensory areas of the perisylvian cortex including the insula and retroinsular cortex, the temporoparietal junction and somatosensory area II receive signals from both sensory channels. We propose that these anatomical sites contribute to egocentric representation of space.

Adult↗

Dopaminergic stimulation in unilateral neglect.

OBJECTIVE: To explore the hypothesis that dopaminergic circuits play a part in the premotor components of the unilateral neglect syndrome, the effects of acute dopaminergic stimulation in patients with neglect were studied. METHODS: Two tasks were evaluated before and after subcutaneous administration of apomorphine and placebo: a circle crossing test and a test of target exploration (a modified version of the bell test), performed both in perceptual (counting) and in perceptual-motor (pointing) conditions. SUBJECTS: Four patients with left neglect. RESULTS: After dopaminergic stimulation, a significant improvement was found compared with placebo administration and baseline evaluation, in the performance of the two tests. Three of the patients had a more marked improvement in the perceptual-motor condition (pointing) of the task than the perceptual condition (counting). CONCLUSIONS: The findings suggest that dopaminergic neuronal networks may mediate, in different ways, both perceptive and premotor components of the unilateral neglect syndrome.

Acute Disease↗

Neuropsychological study during video-EEG recording of successive partial seizures of right temporo-central origin.

A 15-year-old, right-handed boy underwent video-EEG study as a first step in presurgical evaluation for a severe drug-resistant right temporo-central epilepsy. He was monitored while performing neuropsychological tests over a 67-minute period during which 23 brief seizures were recorded. Despite his right-handedness, both inter-ictal and ictal verbal performances were impaired. Analysis of the relationships between the characteristics of the EEG and the neuropsychological results revealed that a worsening in cognitive performances correlated with an increase in inter-ictal abnormalities, particularly when subclinical paroxysms were present; that the cognitive tasks executed peri-ictally were correctly performed in almost 50% of the cases; and that the error rate was higher when a task was presented during or immediately after a seizure rather than before its onset. A Wada test, performed on the basis of the cognitive results, demonstrated right hemisphere dominance for language. Our observations underline the importance of neuropsychological testing in presurgical procedures, and suggest that it should be performed peri-ictally whenever possible.

Adolescent↗

[Cognitive evaluation of patients with temporal epilepsy, candidates for surgery].

We provide a short overview on selected aspects of the neuropsychology of patients with temporal lobe epilepsy candidate to surgery. The possible impairment of verbal and non verbal memory is treated in particular. We also present the neuropsychological test battery that we use for the cognitive assessment of such patients before surgery and in the follow-up phase.

Cognition Disorders↗

Modulation of conscious experience by peripheral sensory stimuli.

Lack of awareness of touch associated with brain damage may transiently recover after stimulation of the vestibular system. We used positron emission tomographic regional cerebral blood flow measurements to study the neurophysiological effect of vestibular stimulation on touch imperception in a subject with a right brain lesion. We tested the hypothesis that the vestibular system aids conscious tactile perception by introducing a bias in the neural system subserving body representation. We show that in normal subjects touch and vestibular signals share projections to the putamen, insula, somatosensory area II, premotor cortex and supramarginal gyrus. In our patient a subset of these regions (right putamen and insula) was spared by the lesion and was maximally active when touch and vestibular stimulations were combined. These results support the suggestion that our phenomenological consciousness is associated with activation in circumscribed brain areas specific to the particular sensation of which we are aware.

Adult↗

Intramodal somaesthetic recognition disorders following right and left hemisphere damage.

A dissociation between apperceptive and associative processing after right and left hemisphere damage, respectively, has been suggested for visual, auditory and visuo-tactile matching tasks. This study was aimed at testing for this dissociation in a purely somaesthetic task. Forty consecutive patients with recent right and left hemispheric vascular lesions and 10 normal controls were studied. The groups were compared on two intramodal somaesthetic matching tasks, consisting of either meaningless shapes (apperceptive recognition) or meaningful objects (associative recognition). In normal controls, no significant difference was found either between the two tests, indicating a similar degree of difficulty, or between hands. An analysis of variance indicated a differential impairment of the two hemisphere-damaged groups on the two tests in comparison with normal controls. Right hemisphere lesions impaired the apperceptive, but not the associative, task, while the reverse occurred after left hemisphere lesions. This double dissociation between side of hemispheric lesion (right and left) and level of recognition impairment (apperceptive and associative) extends the results reported for other sensory modalities to intramodal tactile recognition matching.

Aged↗

Identification of the central vestibular projections in man: a positron emission tomography activation study.

The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation.

Adult↗

The role of the right hemisphere in the interpretation of figurative aspects of language. A positron emission tomography activation study.

We investigated cerebral activity in six normal volunteers using PET to explore the hypothesis that the right hemisphere has a specific role in the interpretation of figurative aspects of language such as metaphors. We also mapped the anatomical structures involved in sentence comprehension. During regional cerebral blood flow measurement subjects were asked to perform three different linguistic tasks: (i) metaphorical comprehension; (ii) literal comprehension of sentences; and (iii) a lexical-decision task. We found that comprehension of sentences compared with the lexical-decision task, induced extensive activation in several regions of the left hemisphere, including the prefrontal and basal frontal cortex, the middle and inferior temporal gyri and temporal pole, the parietal cortex and the precuneus. Comprehension of metaphors was associated with similar activations in the left hemisphere, but in addition, a number of sites were activated in the right hemisphere: the prefrontal cortex, the middle temporal gyrus, the precuneus and the posterior cingulate. We conclude that the interpretation of language involves widespread distributed systems bilaterally with the right hemisphere having a special role in the appreciation of metaphors.

Adult↗

Exploring somatosensory hemineglect by vestibular stimulation.

The effects of vestibular stimulation upon somatosensory deficits or tactile extinction contralateral to a hemispheric lesion were investigated in 20 right brain-damaged patients and 11 left brain-damaged patients. After stimulation, right brain-damaged patients showed a temporary partial recovery from left hemianaesthesia or extinction. Conversely, right somatosensory deficits associated with left brain damage were virtually unaffected by vestibular stimulation. Temporary recovery from somatosensory deficits was independent of the presence of visuo-spatial hemineglect. The suggestion is made that somatosensory deficits and extinction produced by right brain damage have an important non-sensory or perceptual component, that may be positively affected by vestibular stimulation. The mechanisms whereby this treatment may ameliorate somatosensory deficits may involve the restoration of the normal correspondence between somatotopic and egocentric representations of the body.

Adolescent↗

Hemianopia, hemianaesthesia, and hemiplegia after right and left hemisphere damage. A hemispheric difference.

The incidence of somatosensory, visual half-field and motor deficits contralateral to a hemispheric lesion in a continuous series of 154 left brain damaged and 144 right brain damaged stroke patients were investigated. These contralateral disorders were more frequent after lesions of the right hemisphere. This difference cannot be attributed to a bias in patients' selection. It is suggested that left spatial neglect is the factor underlying this hemispheric difference.

Aged↗

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↗