Time filter

Source Type

Rome, Italy

Tombini M.,Biomedical University of Rome | Pellegrino G.,Biomedical University of Rome | Pasqualetti P.,AFaR | Assenza G.,Biomedical University of Rome | And 3 more authors.
Brain Stimulation | Year: 2013

Background: Electromagnetic fields (EMFs) emitted by mobile phones had been shown to increase cortical excitability in healthy subjects following 45 min of continuous exposure on the ipsilateral hemisphere. Objective: Using Transcranial Magnetic Stimulation (TMS), the current study assessed the effects of acute exposure to mobile phone EMFs on the cortical excitability in patients with focal epilepsy. Methods: Ten patients with cryptogenic focal epilepsy originating outside the primary motor area (M1) were studied. Paired-pulse TMS were applied to the M1 of both the hemisphere ipsilateral (IH) and contralateral (CH) to the epileptic focus before and immediately after real/sham exposure to the GSM-EMFs (45 min). The TMS study was carried out in all subjects in three different experimental sessions (IH and CH exposure, sham), 1 week apart, according to a crossover, double-blind and counter-balanced paradigm. Results: The present study clearly demonstrated that an acute and relatively prolonged exposure to GSM-EMFs modulates cortical excitability in patients affected by focal epilepsy; however, in contrast to healthy subjects, these effects were evident only after EMFs exposure over the hemisphere contralateral to the epileptic focus (CH). They were characterized by a significant cortical excitability increase in the exposed hemisphere paired with slight excitability decrease in the other one (IH). Both sham and real EMFs exposure of the IH did not affect brain excitability. Conclusion: Present results suggest a significant interaction between the brain excitability changes induced by EMFs and the epileptic focus, which eliminated the excitability enhancing effects of EMFs evident only in the CH. © 2013 Elsevier Inc. All rights reserved.

Mariani S.,Biomedical University of Rome | Ventriglia M.,Biomedical University of Rome | Simonelli I.,Medical Statistics and Information Technology | Donno S.,Medical Statistics and Information Technology | And 7 more authors.
Neurobiology of Aging | Year: 2013

To evaluate whether iron and copper levels in serum, plasma, and cerebrospinal fluid are disarranged in Parkinson's disease (PD), we performed meta-analyses of 33 studies on the topic published from 1987 to 2011 and contextually carried out a replication study in serum by ourselves as well. We found no variation in metals between PD patients and healthy controls, according to our replication study. The metaregression for sex revealed that serum copper differences found in some studies could be referred to the different percentage of women in the PD sample. Transferrin and transferrin saturation levels found increased in PD subjects underline the concept to extend the iron study in PD to iron master proteins. © 2013 Elsevier Inc.

Vecchio F.,AFaR | Babiloni C.,University of Foggia
International Journal of Alzheimer's Disease | Year: 2011

Is directionality of electroencephalographic (EEG) synchronization abnormal in amnesic mild cognitive impairment (MCI) and Alzheimer's disease (AD)? And, do cerebrovascular and AD lesions represent additive factors in the development of MCI as a putative preclinical stage of AD? Here we reported two studies that tested these hypotheses. EEG data were recorded in normal elderly (Nold), amnesic MCI, and mild AD subjects at rest condition (closed eyes). Direction of information flow within EEG electrode pairs was performed by directed transfer function (DTF) at δ(24Hz), θ(48Hz), α1 (8-10Hz), α2 (10-12Hz), β1 (13-20Hz), β2 (20-30Hz), and (30-40Hz). Parieto-to-frontal direction was stronger in Nold than in MCI and/or AD subjects for and rhythms. In contrast, the directional flow within interhemispheric EEG functional coupling did not discriminate among the groups. More interestingly, this coupling was higher at θ, α1, β2, and β1 in MCI with higher than in MCI with lower vascular load. These results suggest that directionality of parieto-to-frontal EEG synchronization is abnormal not only in AD but also in amnesic MCI, supporting the additive model according to which MCI state would result from the combination of cerebrovascular and neurodegenerative lesions. Copyright © 2011 Fabrizio Vecchio and Claudio Babiloni.

Moretti D.V.,IRCCS S Giovanni di Dio Fatebenefratelli | Frisoni G.B.,IRCCS S Giovanni di Dio Fatebenefratelli | Fracassi C.,IRCCS S Giovanni di Dio Fatebenefratelli | Pievani M.,IRCCS S Giovanni di Dio Fatebenefratelli | And 5 more authors.
Neurobiology of Aging | Year: 2011

The theta/gamma and alpha3/alpha2 ratio were investigated as early markers for prognosticating of progression to dementia. 76 subjects with mild cognitive impairment (MCI) underwent EEG recording, MRI scans and neuropsychological (NPS) tests. After 3 years of follow-up, three subgroups were characterized as converters to Alzheimer's disease (AD, N= 18), converters to non-AD dementia (N= 14) and non-converters (N= 44). The theta/gamma and alpha3/alpha2 ratio, performance on cognitive tests and hippocampal volume, as evaluated at the time of initial MCI diagnosis, were studied in the three groups. As expected, MCI to AD converters had the smallest mean hippocampal volume and poorest performance on verbal learning tests, whereas MCI to non-AD converters had poorest cognitive performance in non-verbal learning tests, abstract thinking, and letter fluency. Increased theta/gamma ratio was associated with conversion to both AD and non-AD dementia; increased alpha3/alpha2 ratio was only associated with conversion to AD. Theta/gamma and alpha3/alpha2 ratio could be promising prognostic markers in MCI patients. In particular, the increase of high alpha frequency seems to be associated with conversion in AD. EEG markers allow a mean correct percentage of correct classification up to 88.3%. Future prospective studies are needed to evaluate the sensitivity and specificity of these measures for predicting an AD outcome. © 2009 Elsevier Inc.

Babiloni C.,University of Foggia | De Pandis M.F.,Casa di Cura san raffaele cassino | Vecchio F.,AFaR | Buffo P.,University of Rome La Sapienza | And 4 more authors.
Clinical Neurophysiology | Year: 2011

Objective: Here we test the hypothesis that cortical source mapping of resting state electroencephalographic (EEG) rhythms could characterize neurodegenerative disorders inducing cognitive impairment such as Parkinson's disease related dementia (PDD) and Alzheimer's disease (AD). Methods: To address this issue, eyes-closed resting state EEG rhythms were recorded in 13 PDD, 20 AD, and 20 normal elderly (Nold) subjects. Age, gender, and education were carefully matched across the three groups. Mini Mental State Evaluation (MMSE) score probed subjects' global cognitive status, and was matched between the PDD and AD groups. EEG rhythms of interest were delta (2-4. Hz), theta (4-8. Hz), alpha1 (8-10.5. Hz), alpha2 (10.5-13. Hz), beta1 (13-20. Hz), and beta2 (20-30. Hz). EEG cortical sources were estimated by low resolution brain electromagnetic source tomography (LORETA). Results: With respect to the Nold and AD groups, the PPD group was characterized by peculiar abnormalities of central delta sources and posterior cortical sources of theta and beta1 rhythms. With respect to the Nold group, the PDD and AD groups mainly pointed to lower posterior cortical sources of alpha1 rhythms, which were positively correlated to MMSE score across all PDD and AD subjects as a whole (the lower the alpha sources, the lower the MMSE score). This alpha decrease was greater in the AD than PPD patients. Conclusions: The results suggest that topography and frequency of eyes-closed resting state cortical EEG rhythms distinguished PDD and AD groups. Significance: We report the existence of different effects of neurodegeneration on the cortical neural synchronization mechanisms generating resting state EEG rhythms in PDD and AD patients. © 2011.

Discover hidden collaborations