Papers by giuseppe caravaglios
Rivista di Neuroradiologia, 2002
Il low back pain è un dolore localizzato a livello lombo-sacrale, eventualmente associato ad irra... more Il low back pain è un dolore localizzato a livello lombo-sacrale, eventualmente associato ad irradiazione radicolare sciatalgica o cruralgica. È uno dei sintomi più frequenti per cui viene consultato un medico. Si tratta di una sindrome ad elevato costo sociale. La regione denominata low-back è composta dalle ultime vertebre lombari, il sacro ed il coccige, le articolazioni sacro-iliache ed intervertebrali, i muscoli, i legamenti, gli elementi nervosi. La patogenesi del dolore lombare può essere meccanica, compressiva, infiammatoria, neuropatica e da somatizzazione. Le patologie più frequentemente riscontrate sono quella vertebrale degenerativa e quella discale. Il dolore è il sintomo più importante. Se la sintomatologia è persistente, si accompagna a segni neurologici obiettivi e a segni sistemici d'infezione o di neoplasia, è opportuno procedere con esami di laboratorio e radiologici. Gli esami neurofisiologici sono utili in caso di deficit neurologici evidenti od estesi. Il m...
Clinical EEG and neuroscience, Jan 2, 2016
Recent studies demonstrated that beta oscillations are elicited during cognitive processes. To in... more Recent studies demonstrated that beta oscillations are elicited during cognitive processes. To investigate their potential as electrophysiological markers of amnestic mild cognitive impairment (aMCI), we recorded beta EEG activity during resting and during an omitted tone task in patients and healthy elderly. Thirty participants were enrolled (15 patients, 15 healthy controls). In particular, we investigated event-related spectral perturbation and intertrial coherence indices. Analyses showed that (a) healthy elderly presented greater beta power at rest than patients with aMCI patients; (b) during the task, healthy elderly were more accurate than aMCI patients and presented greater beta power than aMCI patients; (c) both groups showed qualitatively similar spectral perturbation responses during the task, but different spatiotemporal response patterns; and (d) aMCI patients presented greater beta phase locking than healthy elderly during the task. Results indicate that beta activity ...
Electroencephalography and Clinical Neurophysiology Electromyography and Motor Control, 1995
The aim of this study was to evaluate early nervous system changes in neurologically asymptomatic... more The aim of this study was to evaluate early nervous system changes in neurologically asymptomatic HIV positive patients by multimodal evoked potentials (VEPs, BAEPs, P300, median and tibial nerve SSEPs). We selected 30 subjects (19 men, 11 women, mean age 31.5 yrs) with HIV infection at CDC stages II, III, IVC2 and IVE without neurological symptoms. We present the results of baseline and follow-up visits: the data of 25 subjects at 6-month, 12 at 12-month and 8 at 18-month controls are at present available. Mean neurophysiologic data were compared by Student's t-test. VEPs, BAEPs and P300 results were normal. Median nerve SSEPs showed a prolonged N9-N13 difference (p < 0.05) at 6-and 12month follow-up visits and a reduction in amplitude of N20 wave (p < 0.005) at 12-and 18-month follow-up visits. Tibial nerve SSEPs showed a prolonged latency of P40 wave (p < 0.02) and an increase of central conduction time (p < 0.01) at 6-and 12-month follow-up. No changes occurred for P300 values throughout the study. None of the patients evaluated disclosed overt neurological symptoms or signs nor superior function abnormalities during the study, with the exception of one case of DDC-induced neuropathy. These partial data suggest that subclinical alterations of central and peripheral nervous system, the appearance of which is well documented in the course of HIV infection, can be evaluated by SSEP study also in early stages of the disease. The usefulness of BAEE VEP and P300 study for the early diagnosis of neurological alterations remains however to be ascertained.
Journal of Neural Transmission, Sep 16, 2010
There is evidence that theta responses reflect cognitive performance: good performances are assoc... more There is evidence that theta responses reflect cognitive performance: good performances are associated with a decrease in tonic theta power as well as an increase in phasic theta power. In the present study, both tonic and phasic theta activity were analysed in 22 patients with mild Alzheimer&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s disease (AD), and 16 healthy elderly controls. Single-trial theta power responses were evaluated by an active auditory oddball paradigm along an early poststimulus window (0-250 ms) and a late time window (250-500 ms), and then compared to prestimulus theta power during both target tone and standard tone processing. The main findings were: (1) in AD patients, there was an increased prestimulus theta power, as well as no significant poststimulus theta power increase upon both target and non-target stimulus processing; (2) in healthy aged controls, only during target tone processing, an enhancement of both early and late theta responses relative to the prestimulus baseline was found. Moreover, healthy controls had a frontal dominance of theta power. The results might indicate that, during target processing, theta response is not functionally sensitive in AD and cannot be involved in processing demands as efficiently as in healthy controls. From a psychophysiological point of view, this might suggest an impairment of attentional allocation resources. The psychological implications might be related to selective attention/working-memory impairment from the early stage of the disease. Our data confirm that both tonic and phasic theta are relevant indicators of cognitive performance: the lack of a phasic theta and an increase in tonic theta are congruous findings in cognitive decline. Another factor worth noting is that in AD patients theta response is not dominant at the frontal site (as observed in healthy controls), indicating a weaker frontal lobe network reactivity during stimulus processing.
Neuropsychological Trends, 2015
Balint syndrome is characterized by a severe disturbance of visual spatial analysis including imp... more Balint syndrome is characterized by a severe disturbance of visual spatial analysis including impaired oculomotor behaviour, optic ataxia, and simultanagnosia. The complete syndrome is relatively rare, and partial syndromes have been reported more frequently. The present study aims to describe a case of Balint syndrome who displayed all the three main neuropsychological features as a consequence of infarction in the watershed between the anterior and posterior cerebral artery territories. In this case report three days post stroke the clinical assessment showed a severe impairment in several visual spatial tasks (e.g., reading, writing, description of a visual scene, voluntary gaze-shift). Twelve weeks post-stroke the clinical assessment showed a significant improvement in reading, writing, as well as in verbal delayed recall processes, but only a mild improvement in visual spatial tasks like the description of a complex visual scene was registered. Balint's syndrome is rare and is not easy to assess with standard clinical tools. The classical neurological examination evaluates in detail the senses, motility, balance, and to some extent language, but, sometimes, it is much less concerned with
Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control, 1995
The aim of this study was to evaluate early nervous system changes in neurologically asymptomatic... more The aim of this study was to evaluate early nervous system changes in neurologically asymptomatic HIV positive patients by multimodal evoked potentials (VEPs, BAEPs, P300, median and tibial nerve SSEPs). We selected 30 subjects (19 men, 11 women, mean age 31.5 yrs) with HIV infection at CDC stages II, III, IVC2 and IVE without neurological symptoms. We present the results of baseline and follow-up visits: the data of 25 subjects at 6-month, 12 at 12-month and 8 at 18-month controls are at present available. Mean neurophysiologic data were compared by Student's t-test. VEPs, BAEPs and P300 results were normal. Median nerve SSEPs showed a prolonged N9-N13 difference (p < 0.05) at 6-and 12month follow-up visits and a reduction in amplitude of N20 wave (p < 0.005) at 12-and 18-month follow-up visits. Tibial nerve SSEPs showed a prolonged latency of P40 wave (p < 0.02) and an increase of central conduction time (p < 0.01) at 6-and 12-month follow-up. No changes occurred for P300 values throughout the study. None of the patients evaluated disclosed overt neurological symptoms or signs nor superior function abnormalities during the study, with the exception of one case of DDC-induced neuropathy. These partial data suggest that subclinical alterations of central and peripheral nervous system, the appearance of which is well documented in the course of HIV infection, can be evaluated by SSEP study also in early stages of the disease. The usefulness of BAEE VEP and P300 study for the early diagnosis of neurological alterations remains however to be ascertained.
Auditory event-related potentials (AERPs) were recorded during an auditory oddball paradigm in 10... more Auditory event-related potentials (AERPs) were recorded during an auditory oddball paradigm in 108 epileptics and in 32 healthy controls. P300 latency varied in relationship with age only in controls. Symptomatic epileptics had significantly prolonged P300 mean latency compared to those without detectable brain lesion(s) on MR scan. Moreover, these latter patients were compared on the basis of epilepsy duration, type of seizure, seizure frequency and antiepileptic treatment; the application of a multiple regression model showed a significant relationship between P300 latency prolongation and epilepsy duration, seizure frequency and polytherapy. © 2001 Éditions scientifiques et médicales Elsevier SAS cognitive impairment / epilepsy / event-related potentials / P300 Résumé-Potentiels auditifs cognitifs dans l'épilepsie. Les potentiels auditifs de type cognitif (P300) ont été évalués chez 108 patients épileptiques et chez 32 individus sains. La latence du P300 changeait en fonction de l'âge du sujet chez les témoins, et non chez les sujets épileptiques. La latence du P300 était significativement allongée chez les épileptiques symptomatiques par rapport aux épilepsies non symptomatiques. De plus, les patients qui ne présentaient pas de lésions cérébrales à l'IRM ont été comparés sur la base des facteurs de risque suivants : durée du syndrome épileptique, séméiologie des attaques, fréquence des attaques et traitement anti-épileptique. Une latence du P300 significativement plus longue a été trouvée chez les patients présentant un syndrome épileptique de longue durée, des crises fréquentes et traités par polythérapie. © 2001 Éditions scientifiques et médicales Elsevier SAS dysfonction cognitive / épilepsie / potentiels auditifs de type cognitif / P300
Electromyography and clinical neurophysiology, 1999
A neurophysiological (SEP, VEP) follow-up study was carried out in 30 diabetic patients with type... more A neurophysiological (SEP, VEP) follow-up study was carried out in 30 diabetic patients with type I diabetes mellitus of ten or more years duration. This in order to investigate whether one year of improved glucoregulation may influence the progression of central damage. In our series, patients showed a significant decrement of HbA1C levels (p < 0.05) in the one-year follow-up. In the same period the frequency of SEP and VEP abnormalities varied from 10/30 (33%) to 16/30 (53%) and from 8/30 (26%) to 5/30 (16%) respectively. This finding would suggest that prevailing glycaemic control would be a major determinant for the outcome of VEP measurements. SEP alterations, in contrast, tend to progress in a 12 months period despite a considerable improvement in glycaemic control. However, by dividing patients in two groups according mean one year HbA1C less than 8% and more than 8%, the latter group only showed a significant increasing of absolute latencies of each median and tibial SEP ...
Electromyography and clinical neurophysiology
We performed clinical, radiological (MRI) and neurophysiological (NCV, SEPs, and BAEPs) investiga... more We performed clinical, radiological (MRI) and neurophysiological (NCV, SEPs, and BAEPs) investigations in 36 unselected patients affected by Systemic Lupus Erythematosus (SLE). Fifteen patients (42%) presented clear neurological events and were considered as definite neuropsychiatric lupus (NPLE); 21 (58%) presented minor subjective complaints or no neurological problems referable to SLE and were considered as no-NPLE. Twenty-three patients (64%) showed neurophysiological abnormalities: 21 (58%) presented central abnormal neurophysiological measurements (including SEP and BAEP values), while 17 (47%) has slowed peripheral nerve conduction. Twenty-six out of 36 patients executed brain MRI examination. High intensity spots (HIS) in deep or subcortical white matter were the most common abnormalities and were present in 19 of the 26 patients (73%). We found that the incidence of neurophysiological and radiological abnormalities did not significantly differ in neurologically symptomatic ...
Rivista di neurologia
The habenula, an epithalamic structure considered as a part of the limbic system, is able to cont... more The habenula, an epithalamic structure considered as a part of the limbic system, is able to control interictal activity of the hippocampus. Its influence seems to be facilitatory and to have the raphé as a relay station. Habenular action might putatively be ascribed to activation of the serotonergic system.
Journal of neural transmission (Vienna, Austria : 1996), 2015
There are several evidences indicating that an impairment in attention-executive functions is pre... more There are several evidences indicating that an impairment in attention-executive functions is present in prodromal Alzheimer's disease and predict future global cognitive decline. In particular, the issue of temporal orienting of attention in patients with mild cognitive impairment (MCI) due to Alzheimer's disease has been overlooked. The present research aimed to explore whether subtle deficits of cortical activation are present in these patients early in the course of the disease. We studied the upper-alpha event-related synchronization/desynchronization phenomenon during a paradigm of temporal orientation of attention. MCI patients (n = 27) and healthy elderly controls (n = 15) performed a task in which periodically omitted tones had to be predicted and their virtual onset time had to be marked by pressing a button. Single-trial responses were measured, respectively, before and after the motor response. Then, upper-alpha responses were compared to upper-alpha power during...
Journal of Epilepsy, 1996
... M Giroud, P Gras, H Fayolle, N André, P Soichot and R Dumar, Early seizures after acute strok... more ... M Giroud, P Gras, H Fayolle, N André, P Soichot and R Dumar, Early seizures after acute stroke: a study of 1,640 cases, Epilepsia ... PR Dodge, EP Richardson and M Victor, Recurrent convulsive seizures as a sequel to cerebral infarction: a clinical and pathologic study, Brain 77 ...
Pharmacological Research Communications, 1988
Neuroscience Letters, 1994
Many experimental observations have demonstrated the modulatory role exerted by several neural st... more Many experimental observations have demonstrated the modulatory role exerted by several neural structures and neurotransmitters on spontaneous and paroxysmal bioelectric activity of the hippocampus. Recently, the control exerted by locus coeruleus (LC) and its noradrenergic (NA) efferent pathway on different experimental models of epilepsy (e.g. cortical cobalt chronic epilepsy, amygdaloid and hippocampal kindling) was emphasised. On this basis, a series of experiments was perlbrmed to elucidate the functional role of LC-NA system on the hippocampal penicillin (PCN) focus and the type of adrenergic receptor involved. The experiments were carried out on 25 rats in which an epileptiform hippocampal focus was obtained through intrahippocampal PCN administration (100-200 I.U.). In these conditions, LC, ipsilateral to PCN hippocampal focus, was stimulated before and alter intraperitoneal (i.p,) administration of a fl-adrenergic receptor antagonist propranolol (2 mg/kg). Results showed a significant reduction of hippocampal spiking frequency during LC stimulation; after i.p. propranolol injection, LC stimulation, at the same parameters, failed to induce any sort of modification of PCN hippocampal spiking frequency. Furthermore, intrahippocampal application of a fl-selective agonist 2-fluoro-noradrenaline (2-FNA) mimics the inhibitory effects of EC stimulation. All data suggest that the LC-NA system is able to induce a net reduction of hippocampal epileptiform focus and the inhibitory NA control involves the activation of adrenergic beta receptors.
Neurophysiologie Clinique/Clinical Neurophysiology, 2001
Auditory event-related potentials (AERPs) were recorded during an auditory oddball paradigm in 10... more Auditory event-related potentials (AERPs) were recorded during an auditory oddball paradigm in 108 epileptics and in 32 healthy controls. P300 latency varied in relationship with age only in controls. Symptomatic epileptics had significantly prolonged P300 mean latency compared to those without detectable brain lesion(s) on MR scan. Moreover, these latter patients were compared on the basis of epilepsy duration, type of seizure, seizure frequency and antiepileptic treatment; the application of a multiple regression model showed a significant relationship between P300 latency prolongation and epilepsy duration, seizure frequency and polytherapy. © 2001 Éditions scientifiques et médicales Elsevier SAS cognitive impairment / epilepsy / event-related potentials / P300 Résumé -Potentiels auditifs cognitifs dans l'épilepsie. Les potentiels auditifs de type cognitif (P300) ont été évalués chez 108 patients épileptiques et chez 32 individus sains. La latence du P300 changeait en fonction de l'âge du sujet chez les témoins, et non chez les sujets épileptiques. La latence du P300 était significativement allongée chez les épileptiques symptomatiques par rapport aux épilepsies non symptomatiques. De plus, les patients qui ne présentaient pas de lésions cérébrales à l'IRM ont été comparés sur la base des facteurs de risque suivants : durée du syndrome épileptique, séméiologie des attaques, fréquence des attaques et traitement anti-épileptique. Une latence du P300 significativement plus longue a été trouvée chez les patients présentant un syndrome épileptique de longue durée, des crises fréquentes et traités par polythérapie. © 2001 Éditions scientifiques et médicales Elsevier SAS dysfonction cognitive / épilepsie / potentiels auditifs de type cognitif / P300
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Papers by giuseppe caravaglios