B Fierro

Università degli Studi di Palermo, Palermo, Sicily, Italy

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Publications (131)245.08 Total impact

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    ABSTRACT: Cortical excitability was investigated in patients with episodic cluster headache.•Motor cortical hyperexcitability was shown in patients both inside and outside bout.•Cortical excitability was asymmetric between the hemispheres.•Greater responses to TMS were shown in the hemisphere ipsilateral to the pain side.•Abnormal cortical excitability may play a role in cluster headache pathophysiology.
    The Journal of Pain. 10/2014;
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    ABSTRACT: Several studies have shown that transcranial direct current stimulation (tDCS) is able to enhance performances on verbal and visual working memory (WM) tasks. Available evidence points to the right dorsolateral prefrontal cortex (DLPFC) as a critical area in visual WM, but to date direct comparisons of the effects obtained by stimulating the left versus the right DLPFC in the same subject are lacking. Our aim was to determine whether tDCS over the right DLPFC can differently affect performance as compared with left DLPFC stimulation. Ten healthy subjects performed a memory-guided visuospatial task in three conditions: baseline, during anodal stimulation applied over the right and during anodal stimulation applied over the left DLPFC. All the subjects also underwent a sham stimulation as control. Our results show that only active stimulation over the right DLPFC is able to increase performance when compared to the other conditions. Our findings confirm the crucial role played by the right DLPFC in spatial WM tasks.
    Functional neurology 10/2014; · 1.86 Impact Factor
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    ABSTRACT: Background Transcranial direct current stimulation (tDCS) is a non-invasive technique used for modulating cortical excitability in vivo in humans. Here we evaluated the effect of tDCS on behavioral and electrophysiological aspects of physiological sucking and swallowing. Methods Twelve healthy subjects underwent three tDCS sessions (anodal, cathodal and sham stimulation) on separate days in a double-blind randomized order. The active electrode was placed over the right swallowing motor cortex. Repeated sucking and swallowing acts were performed at baseline and at 15 and 60 min after each tDCS session and the mean liquid bolus volume ingested at each time point was measured. We also calculated average values of the following electrophysiological parameters: 1) area and 2) duration of the rectified EMG signal from the suprahyoid/submental muscles related to the sucking and swallowing phases; 3) EMG peak amplitude for the sucking and swallowing phases; 4) area and peak amplitude of the laryngeal-pharyngeal mechanogram; 5) oropharyngeal delay. Results The volume of the ingested bolus significantly increased (by an average of about 30% compared with the baseline value) both at 15 and at 60 min after the end of anodal tDCS. The electrophysiological evaluation after anodal tDCS showed a significant increase in area and duration of the sucking phase-related EMG signal. Conclusions Anodal tDCS leads to stronger sucking of a liquid bolus in healthy subjects, likely by increasing recruitment of cortical areas of the swallowing network. This finding might open up interesting perspectives for the treatment of patients suffering from dysphagia due to various pathological conditions.
    Brain Stimulation 09/2014; · 4.54 Impact Factor
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    ABSTRACT: Abnormal increased cortical responsivity to various types of stimuli plays a major role in migraine pathogenesis. Neurophysiological studies, however, have provided ambiguous findings of either hypo or hyper cortical excitability. This is why the term “dysexcitability” has been recently proposed to indicate a more general dysregulation of cortical excitability. The aims of this review are: 1) to provide existing knowledge and research advances in migraine pathophysiology; 2) to propose a unitary interpretation of apparently conflicting neurophysiological findings. Data of studies conducted in migraine through various evoked potentials techniques and non-invasive brain stimulation methods are reviewed, and in some cases reinterpreted according to more recent findings on migraine pathophysiology. In particular, we emphasize the concept that various methods of testing brain excitability may induce different degrees of cortical activation depending on the stimulus parameters used (e.g., intensity, frequency, and duration of stimulation), so shedding light on different pathophysiological aspects. Finally, we try to reconcile apparently conflicting neurophysiological data in the light of a unitary pathophysiological model, suggesting that a condition of interictal cortical hyperresponsivity, possibly due to a glutamatergic dysfunction, could represent the primum movens of migraine pathogenesis.
    Clinical Neurophysiology 09/2014; · 3.14 Impact Factor
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    ABSTRACT: In the past few years, noninvasive cerebral stimulations have been used to modulate language task performance in healthy and aphasic patients. In this study, a dual transcranial direct current stimulation (tDCS) on anterior and posterior language areas was applied for 2 weeks to a patient with a possible crossed aphasia following a right hemisphere stroke. Inhibitory cathodal stimulation of the right Brodmann areas (BA) 44/45 and simultaneous anodal stimulation of the left BA 44/45 improved the patient's performance in picture naming. Conversely, the same bilateral montage on BA 39/40 did not produce any significant improvement; finally, electrode polarity inversion over BA 39/40 yielded a further improvement compared with the first anterior stimulation. Our findings suggest that ipsilesional and contralesional areas could be useful in poststroke functional reorganization and provide new evidences for the therapeutic value of tDCS in aphasia.
    Neurocase 06/2014; · 1.05 Impact Factor
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    ABSTRACT: Dear Editor,Pisa Syndrome (PS) is clinically defined as a pronounced lateral flexion of the trunk (at least 10°), completely alleviated by passive mobilization or on lying supine [1]. PS has been described in patients with Parkinson’s disease (PD) and, until now, few studies have pointed out its possible relationship with either clinical evolution of disease and medical treatment. Although pathophysiology of PS still remains largely unexplained a dopaminergic impairment seems to play a major role in its onset. Accordingly, in some PD patients, PS may be triggered by starting of dopamine blocking agents, or by changes in dopaminergic medication (e.g., start of a new drug, and dose increase or decrease of existing medication). In addition, non-dopaminergic medications might also contribute for developing PS such as neuroleptics, lithium carbonate, valproic acid, antidepressants, anti-emetics, and cholinesterase inhibitors [1].Here we describe the case of a 73-year-old woman with a 5-year
    Neurological Sciences 04/2014; · 1.41 Impact Factor
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    ABSTRACT: Background and objectiveProgression of Parkinson's disease (PD) is frequently characterized by the occurrence of freezing of gait (FOG) representing a disabling motor complication. We aim to investigate safety and efficacy of transcranial direct current stimulation of the primary motor cortex of PD patients with FOG.Methods In this cross-over, double-blind, sham-controlled study, 10 PD patients with FOG persisting in “on” state underwent anodal and sham direct current stimulation for 5 consecutive days. Clinical assessment over a 1-month period was performed.ResultsA significant improvement of gait, as assessed by the Stand Walk Sit test, with reduction in number and duration of FOG episodes, along with a significant reduction in the Unified Parkinson's Disease Rating Scale score, were observed after anodal stimulation. Beneficial effects were more evident after the entire 5-day stimulation session, and persisted until the end of the observation period.Conclusions Anodal transcranial direct current stimulation of the motor cortex is safe and has therapeutic potential in PD patients with FOG. © 2014 International Parkinson and Movement Disorder Society
    Movement Disorders 04/2014; · 5.63 Impact Factor
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    ABSTRACT: Neurophysiological studies in migraine have reported conflicting findings of either cortical hyper- or hypoexcitability. In migraine with aura (MwA) patients, we recently documented an inhibitory response to suprathreshold, high-frequency repetitive transcranial magnetic stimulation (hf-rTMS) trains applied to the primary motor cortex, which is in contrast with the facilitatory response observed in the healthy subjects. The aim of the present study was to support the hypothesis that in migraine, because of a condition of basal increased cortical responsivity, inhibitory homeostatic like mechanisms of cortical excitability could be induced by high magnitude stimulation. For this purpose, the hf-rTMS trains were preconditioned by transcranial direct current stimulation (tDCS), a noninvasive brain stimulation technique able to modulate the cortical excitability state. Twenty-two MwA patients and 20 patients with migraine without aura (MwoA) underwent trains of 5-Hz repetitive transcranial magnetic stimulation at an intensity of 130% of the resting motor threshold, both at baseline and after conditioning by 15 minutes of cathodal or anodal tDCS. Motor cortical responses to the hf-rTMS trains were compared with those of 14 healthy subjects. We observed abnormal inhibitory responses to the hf-rTMS trains given at baseline in both MwA and MwoA patients as compared with the healthy subjects (P < .00001).The main result of the study was that cathodal tDCS, which reduces the cortical excitability level, but not anodal tDCS, which increases it, restored the normal facilitatory response to the hf-rTMS trains in both MwA and MwoA. The present findings strengthen the notion that, in migraine with and without aura, the threshold for inducing inhibitory mechanisms of cortical excitability might be lower in the interictal period. This could represent a protective mechanism counteracting cortical hyperresponsivity. Our results could be helpful to explain some conflicting neurophysiological findings in migraine and to get insight into the mechanisms underlying recurrence of the migraine attacks.
    Headache The Journal of Head and Face Pain 04/2014; 54(4):663-74. · 2.94 Impact Factor
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    ABSTRACT: The primary brain dysfunctions leading to the onset of a migraine attack remain largely unknown. Other important open questions concern the mechanisms of initiation, continuation, and termination of migraine pain, and the changes in brain function underlying migraine transformation. Brief trains of high-frequency repetitive transcranial magnetic stimulation (rTMS), when applied to the primary motor cortex at suprathreshold intensity (⩾ 120% of resting motor threshold, RMT), elicit in healthy subjects a progressive, glutamate-dependent facilitation of the Motor Evoked Potentials (MEP). Conversely, in conditions of increased cortical excitability, the rTMS trains induce inhibitory MEP responses likely mediated by cortical homeostatic mechanisms. We enrolled 66 migraine without aura (MwoA) patients, 48 migraine with aura (MwA) patients, 14 patients affected by chronic migraine (CM), and 20 healthy controls. We assessed motor cortical response to 5-Hz rTMS trains of 10 stimuli given at 120% RMT. Patients with episodic migraine (EM) were studied in different phases of the migraine cycle, i.e. interictal, preictal, ictal and postictal state. Results showed a facilitatory MEP response during the trains in patients evaluated in the preictal phase, whilst inhibitory responses were observed during and after a migraine attack, as well as in CM patients. In the interictal phase, different responses were observed depending on attack frequency: facilitation in patients with low and inhibition with those with high attack recurrence. Our findings suggest that changes in cortical excitability and fluctuations in the threshold for inhibitory metaplasticity underlie the migraine attack recurrence, and could be involved in the process of migraine transformation.
    Pain 03/2014; · 5.64 Impact Factor
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    ABSTRACT: Objective To evaluate the effects of transcranial direct current stimulation (tDCS) on esophageal peristalsis in patients with gastroesophageal reflux disease (GERD). Methods Patients with GERD preliminary diagnosis were included in a randomized double-blind sham-controlled study. Esophageal manometry was performed before and during transcranial direct current stimulation (tDCS) of the right precentral cortex. Half of patients were randomly assigned to anodal, half to sham stimulation. Distal waves amplitude and pathological waves percentage were measured, after swallowing water boli, for ten subsequent times. Last, a 24 h pH-bilimetry was done to diagnose non-erosive reflux disease (NERD) or functional heartburn (FH). The values obtained before and during anodal or sham tDCS were compared. Results Sixty-eight patients were enrolled in the study. Distal waves mean amplitude increased significantly only during anodal tDCS in NERD (p = 0.00002) and FH subgroups (p = 0.008) while percentage of pathological waves strongly decreased only in NERDs (p = 0.002). Conclusions Transcranial stimulation can influence cortical control of esophageal motility and improve pathological motor pattern in NERD and FH but not in erosive reflux disease (ERD) patients. Significance Pathophysiological processes in GERD are not only due to peripheral damage but to central neural control involvement as well. In ERD patients dysfunctions of the cortico-esophageal circuit seem to be more severe and may affect central nervous system physiology.
    Clinical Neurophysiology 01/2014; · 3.14 Impact Factor
  • Pain 11/2013; · 5.64 Impact Factor
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    ABSTRACT: Aim: Topiramate is a small molecule widely used for the treatment of epilepsy, migraine, bipolar disorders and alcoholism, and its availability as a generic formulation could significantly reduce the National Health Service expenditure. A generic formulation, available in Italy under the trademark Sincronil, recently showed superimposable blood levels, after oral administration to healthy volunteers, with the reference formulation. In the present study we report the results of an open label, parallel group, randomized, controlled study performed to evaluate the efficacy, tolerability and impact on disability of two different formulations of topiramate (Sincronil and Topamax) in patients with migraine without aura. Methods: Sixty patients aged between 18 and 65 years, suffering from migraine without aura with an attack frequency of 3-15 attacks/month were enrolled and received, after a titration phase lasting 20 days, randomly either Sincronil or Topamax at the dose of 25 mg twice daily for 3 months. Results: Fifteen out of the 30 patients who were administered Sincronil reported an improvement in the clinical condition, with a decrease in the frequency of attacks at the 3rd month of treatment higher than 50% with respect to the run-in period, 9 reported their clinical condition as being substantially unchanged and 6 reported that they had suspended the treatment within the first 4 weeks of therapy due to side effects. Among the 24 patients who continued treatment up to the 3rd month, the frequency of attacks during the 3rd month of treatment was significantly decreased from 7±3.6 to 3.7±3.7 (P<0.0001), migraine severity was reduced from 2.5±0.5 to 1.7±0.7 (P<0.0005) and the MIDAS score was reduced from 14.3±4.9 to 8.6±5.5 (P<0.0001). Sixteen out of the 30 patients who were administered Topamax reported an improvement in the clinical condition with a reduction in the attack frequency at the 3rd month of treatment higher than 50% with respect to the run-in period, 10 reported a substantially unchanged clinical condition and 4 stopped the treatment within the first weeks due to side effects. Among the 26 patients who continued treatment up to the 3rd month, headache frequency during the 3rd month of treatment was significantly reduced, from 7.3±2.6 to 3.5±2.7 (P<0.0001), migraine severity decreased from 2.4±0.6 to 1.6±0.8 (P<0.0005) and the MIDAS score from 14.1±4.2 to 6.8±4.8 (P<0.0001). Conclusion: In conclusion, in this study Topamax (reference product) and Sincronil (generic formulation) have proven therapeutically equivalent and both products were well tolerated.
    Panminerva medica 09/2013; 55(3):303-307. · 2.28 Impact Factor
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    ABSTRACT: Migraine is a very prevalent disease with great individual disability and socioeconomic burden. Despite intensive research effort in recent years, the etiopathogenesis of the disease remains to be elucidated. Recently, much importance has been given to mechanisms underlying the cortical excitability that has been suggested to be dysfunctional in migraine. In recent years, noninvasive brain stimulation techniques based on magnetic fields (transcranial magnetic stimulation, TMS) and on direct electrical currents (transcranial direct current stimulation, tDCS) have been shown to be safe and effective tools to explore the issue of cortical excitability, activation, and plasticity in migraine. Moreover, TMS, repetitive TMS (rTMS), and tDCS, thanks to their ability to interfere with and/or modulate cortical activity inducing plastic, persistent effects, have been also explored as potential therapeutic approaches, opening an interesting perspective for noninvasive neurostimulation for both symptomatic and preventive treatment of migraine and other types of headache. In this chapter we critically review evidence regarding the role of noninvasive brain stimulation in the pathophysiology and treatment of migraine, delineating the advantages and limits of these techniques together with potential development and future application.
    Handbook of Clinical Neurology 01/2013; 116C:585-598.
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    13th World Congress of the International Society for Diseases of the Esophagus.; 10/2012
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    European Federations of Neurological Societies (EFNS); 09/2012
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    ABSTRACT: The objective of the study was to compare the efficacy and safety of frovatriptan and almotriptan in women with menstrually related migraine (IHS Classification of Headache disorders) enrolled in a multicenter, randomized, double-blind, cross-over study. Patients received frovatriptan 2.5 mg or almotriptan 12.5 mg in a randomized sequence: after treating 3 episodes of migraine in no more than 3 months with the first treatment, the patient was switched to the other treatment. 67 of the 96 female patients of the intention-to-treat population of the main study had regular menstrual cycles and were thus included in this subgroup analysis. 77 migraine attacks classified as related to menses were treated with frovatriptan and 78 with almotriptan. Rate of pain relief at 2 and 4 h was 36 and 53 % for frovatriptan and 41 and 50 % for almotriptan (p = NS between treatments). Rate of pain free at 2 and 4 h was 19 and 47 % with frovatriptan and 29 and 54 % for almotriptan (p = NS). At 24 h, 62 % of frovatriptan-treated and 67 % of almotriptan-treated patients had pain relief, while 60 versus 67 % were pain free (p = NS). Recurrence at 24 h was significantly (p < 0.05) lower with frovatriptan (8 vs. 21 % almotriptan). This was the case also at 48 h (9 vs. 24 %, p < 0.05). Frovatriptan was as effective as almotriptan in the immediate treatment of menstrually related migraine attacks. However, it showed a more favorable sustained effect, as shown by a lower rate of migraine recurrence.
    The Journal of Headache and Pain 05/2012; 13(5):401-6. · 2.78 Impact Factor
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    ABSTRACT: Experimental studies emphasize the importance of homeostatic plasticity as a mean of stabilizing the properties of neural circuits. In the present work we combined two techniques able to produce short-term (5-Hz repetitive transcranial magnetic stimulation, rTMS) and long-term (transcranial direct current stimulation, tDCS) effects on corticospinal excitability to evaluate whether and how the effects of 5-Hz rTMS can be tuned by tDCS preconditioning. Twelve healthy subjects participated in the study. Brief trains of 5-Hz rTMS were applied to the primary motor cortex at an intensity of 120% of the resting motor threshold, with recording of the electromyograph traces evoked by each stimulus of the train from the contralateral abductor pollicis brevis muscle. This interventional protocol was preconditioned by 15 min of anodal or cathodal tDCS delivered at 1.5 mA intensity. Our results showed that motor-evoked potentials (MEPs) increased significantly in size during trains of 5-Hz rTMS in the absence of tDCS preconditioning. After facilitatory preconditioning with anodal tDCS, 5-Hz rTMS failed to produce progressive MEP facilitation. Conversely, when 5-Hz rTMS was preceded by inhibitory cathodal tDCS, MEP facilitation was not abolished. These findings may give insight into the mechanisms of homeostatic plasticity in the human cerebral cortex, suggesting also more suitable applications of tDCS in a clinical setting.
    European Journal of Neuroscience 01/2012; 35(1):119-24. · 3.75 Impact Factor
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    The Journal of Headache and Pain 10/2011; · 2.78 Impact Factor
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    ABSTRACT: Repetitive transcranial magnetic stimulation (rTMS) over right posterior parietal cortex was shown to induce interference on visuospatial perception in healthy subjects. Transcranial direct current stimulation (tDCS) is another noninvasive brain stimulation technique that works modulating cortical activity. It is applied through easy to use, noncostly, and portable devices. The aim of the current study was to investigate if the novel approach of "dual" stimulation over parietal cortices compared with the unilateral (right) cathodal one is able to induce greater and/or longer-lasting neglect-like effects in normal subjects performing a computerized visuospatial task. Eleven healthy subjects underwent a computerized visuospatial task requiring judgments about the symmetry of prebisected lines in baseline condition, during and after tDCS. Right cathodal and left anodal tDCS were simultaneously applied over homologue posterior parietal cortices in the "dual" approach, whereas right cathodal tDCS was used in the traditional unihemisphere stimulation. A significant rightward bias in symmetry judgments as compared with baseline and sham conditions was observed in both the stimulation approaches. With "dual" tDCS compared with cathodal stimulation the effect was stronger and appeared earlier, but no longer-lasting after effects were found. We speculate that the resulting modulation of interhemispheric inhibition mediated the additional rightward bias in task performance for "dual" hemisphere compared with unihemisphere tDCS. If "dual" tDCS may better reproduce mechanisms underlying real lesions, it could provide a more suitable model for rehabilitation of negligent patients.
    Brain Stimulation 10/2011; 4(4):294-9. · 4.54 Impact Factor
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    European Federation of Autonomic Societies 2011; 09/2011

Publication Stats

2k Citations
245.08 Total Impact Points


  • 1984–2014
    • Università degli Studi di Palermo
      • • Department of experimental medicine and clinical neurosciences
      • • Dipartimento di Psicologia
      Palermo, Sicily, Italy
  • 2012
    • Università Politecnica delle Marche
      Ancona, The Marches, Italy
  • 2011
    • Università degli Studi G. d'Annunzio Chieti e Pescara
      • Dipartimento di Medicina e Scienze dell'Invecchiamento
      Chieta, Abruzzo, Italy
  • 2007
    • Università degli Studi di Trento
      • Department of Psychology and Cognitive Science
      Trento, Trentino-Alto Adige, Italy