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E Bonanni

Publications and source records attributed to E Bonanni.

16 recordsLinked to original sources
PubMed2006

Quantitative EEG analysis in post-traumatic anosmia.

Many objective and quantitative methods have been developed to create a procedure or a device to prove, describe and quantify olfactory deficit and anosmia, especially after a head trauma. Electrophysiological testing throughout olfactoelectroencephalography (olfactoEEG) is based on brain activity desynchronisation, and on the subsequent disappearance of alpha activity on the posterior regions after an olfactory stimulus. Yet traditional evaluation of EEG can be difficult, because of little or hardly detectable alpha activity on the posterior regions ('alpha rare'). The aim of this study was to evaluate the Olfactory Stop Reaction (OSR) by means of frequency band power calculation and subsequent topographical mapping in patients with post-traumatic anosmia, who presented 'alpha rare' EEG. Twenty-five consecutive patients, affected by anosmia caused by head trauma, were submitted to an EEG recording with olfactory stimulation. After signal processing and analysis, an Olfactory Stop Reaction was detected in 17 out of 25 patients; moreover, in these patients we detected a significant decrease in alpha band power in the occipital regions and an increase in theta band power on midline frontal and central regions after olfactory stimulation. In the remaining eight patients, no significant variation in band power was observed. In conclusion, an objective evaluation of the olfactory function with this method of automatic EEG signal analysis allows the limits given by psychophysical methods and traditional EEG to be overcome and attempts to fulfil the requirements for standardization of olfactory function evalution.

Adult↗
PubMed2005

Rizatriptan does not change cerebral blood flow velocity during migraine attacks.

Rizatriptan represents a major advance in the treatment of migraine attack: inhibition of peripheral trigeminal nerve and constriction of intracranial extracerebral blood vessels have been proposed as its main antimigraine mechanisms of action. Although many studies may suggest that rizatriptan causes highly selective vasoconstriction within intracranial extracerebral vessels (i.e., meningeal arteries), no literature data are available to date on possible cerebral hemodynamic changes in humans after treatment with rizatriptan. The aim of this study was to evaluate the effect of rizatriptan on cerebral blood flow velocity performing transcranial Doppler during spontaneous attacks of migraine without aura. Fourteen patients suffering from migraine without aura were monitored to evaluate mean flow velocity changes on both middle cerebral arteries during migraine attack 30 min before and 120 min after oral administration of rizatriptan 10mg. Monitoring was repeated for 30 min during the pain-free period. All patients turned out to be drug responders and no significant mean flow velocity changes were observed between the pain-free period and pre-treatment phase; besides no significant difference in mean flow velocity value have been detected between the periods after the drug administration during the attack versus both pre-treatment period and pain-free phase. These findings indicate that the antimigraine action of rizatriptan is not associated with clear intracranial cerebral hemodynamic changes and may support its cerebrovascular safety.

Adult↗
PubMed2005

Effects of prolonged wakefulness combined with alcohol and hands-free cell phone divided attention tasks on simulated driving.

Simulated driving ability was assessed following administration of alcohol, at an estimated blood level of 0.05%, and combined prolonged wakefulness, while participants were undertaking divided attention tasks over a hands-free mobile phone. Divided attention tasks were structured to provide a sustained cognitive workload to the subjects. Twenty three young healthy individuals drove 10 km simulated driving under four conditions in a counterbalanced, within-subject design: alcohol, alcohol and 19 h wakefulness, alcohol and 24 h wakefulness, and while sober. Study measures were: simulated driving, self-reported sleepiness, critical flicker fusion threshold (CFFT), Stroop word-colour interference test (Stroop) and simple visual reaction times (SVRT). As expected, subjective sleepiness was highly correlated with both sleep restriction and alcohol consumption. The combination of alcohol and 24 h sustained wakefulness produced the highest driving impairment, significantly beyond the alcohol effect itself. Concurrent alcohol and 19 h wakefulness significantly affected only driving time-to-collision. No significant changes of study measures occurred following alcohol intake in unrestricted sleep conditions. CFFT, SVRT and Stroop results showed a similar trend in the four study conditions. Thus apparently 'safe' blood alcohol levels in combination with prolonged wakefulness resulted in significant driving impairments. In normal sleep conditions alcohol effects on driving were partially counteracted by the concomitant hands-free phone based psychometric tasks.

Accidents, Traffic↗
PubMed2002

Lormetazepam effects on daytime vigilance, psychomotor performance and simulated driving in young adult healthy volunteers.

OBJECTIVE: To assess the residual effects of lormetazepam on daytime vigilance, psychomotor performance and simulated driving in adult healthy volunteers. MATERIAL: Twelve subjects (7 women, 5 men), aged 27 - 38 years (mean 31). METHOD: Subjects received lormetazepam 1 mg tablet and placebo for 3 days at nighttime in a randomized, double-blind, crossover design, with a 1-week interval between medications. On the morning following the last drug administration, the subjects completed a 15-min battery of neuropsychological tests aimed at assessing memory and attention, performed simple and choice visual reaction times, and self-rated their own level of sleepiness using the Epworth sleepiness scale. Afterwards, an interactive, computer-based driving simulator (STISIM) was used to assess the effect of the study drugs on driving ability, followed by the multiple sleep latency test (MSLT). RESULTS: The findings showed that participants had similar performance when treated with lormetazepam and placebo. Indeed, as compared with baseline, neuropsychological tests, visual reaction times, sleep latency using the MSLT and driving ability showed no deterioration following either placebo or active medication. CONCLUSIONS: The data suggest that 3-day use of lormetazepam 1 mg/day neither influences daytime vigilance nor impairs psychomotor task performance and simulated driving. Results confirm previous evidence that the intermediate-acting hypnotic benzodiazepine lormetazepam is devoid of residual effects in respect to psychomotor ability. However, caution should be exercised in the interpretation of the results due to the limited sensitivity of the study.

Adult↗
PubMed2001

The importance of nasal resistance in obstructive sleep apnea syndrome: a study with positional rhinomanometry.

The importance of nasal obstruction in the pathogenesis of obstructive sleep apnea syndrome (OSAS) has not yet been totally defined. Numerous studies have reported an association between nasal obstruction and OSAS, but the precise nature of this relationship remains to be clarified. This study was undertaken to evaluate the prevalence of nasal obstruction disorders in a group of OSAS patients. For this purpose, we analyzed the nasal resistance of 36 OSAS patients by performing a traditional basal anterior active rhinomanometry test (AAR) and a positional AAR, with the patient in a supine position. Seven patients had a pathologic nasal resistance in the seated position that increased further in the supine position; 9 patients had normal resistance in the seated position but a pathologic resistance in the supine position. In 20 patients, nasal resistance was normal in both positions. No statistically significant differences in the degree of apnea/hypopnea index (AHI) was found between the 20 patients with normal positional AAR and the 16 with pathologic positional AAR (p = 0.13). Moreover, no statistically significant differences in the degree of AHI was found between the 7 patients with pathologic basal and positional AAR and the 9 patients with normal basal AAR and pathologic positional AAR (p = 0.38).

Adult↗
PubMed2001

Neurophysiological evaluation of vigilance in epileptic patients on monotherapy with lamotrigine.

OBJECTIVE: Limited research has focused to date on daytime sleepiness in epileptic patients treated with either conventional or newer antiepileptic drugs. We evaluated the level of vigilance in 15 consecutive, newly diagnosed and never medicated adult epileptic patients, receiving initial monotherapy with lamotrigine (LTG). METHODS: Patients underwent the Multiple Sleep Latency Test (MSLT), visual reaction times (VRT) and Stanford Sleepiness Scale (SSS) on two separate occasions, i.e. before and 2 months after LTG treatment. A group of 15 age-matched healthy volunteers was taken as control. RESULTS: At baseline, mean sleep latencies on the MSLT were comparable in epileptic patients and in controls. In patients, 2 months after monotherapy with LTG 200 mg/day, MSLT scores did not significantly change as compared with pre-treatment values. Accordingly, subjective evaluation of vigilance by the SSS and psychomotor performance by VRT were superimposable in controls and in untreated patients, and did not change in patients after LTG treatment. CONCLUSIONS: These results suggest that in adult, newly diagnosed epileptic patients initial monotherapy with LTG does not impair vigilance.

Adult↗
PubMed2001

Asymmetric scalp distribution of pattern visual evoked potentials during interictal phases in migraine.

The N70 and P100 components of transient pattern visual evoked potentials (P-VEPs) were measured in migraine patients, with and without aura, and in normal subjects in order to evaluate their latency, amplitude and occipital scalp distribution. The aim was to find any typical electrophysiological abnormalities in migraine. P-VEP N70 and P100 were analyzed in 59 patients without any known visual field defect. Mean latency and amplitude values were within normal ranges for either N70 and P100 all over the occipital scalp; the only significant abnormality we found was related to the absolute right-left amplitude ratio either for N70 and P100 waves, providing an asymmetry in P-VEP scalp distribution; this finding was detected in 78.9% of patients with aura and 72.5% without aura. Our results show that in migraine patients, both P-VEP waves N70 and P100, have an asymmetric topographic distribution, even during interictal phases, that can be explained by a cortical disturbance in agreement with the neural hypothesis of headache.

Adult↗
PubMed2000

Peripheral-type benzodiazepine receptors in human blood cells of patients affected by migraine without aura.

The kinetic parameters at equilibrium of peripheral benzodiazepine receptors in platelets, lymphocytes and granulocytes of 15 patients affected by migraine without aura were tested using [3H]PK 11195, a specific radioligand for this receptor and compared with the same number of healthy controls: a statistically significant increase (platelets 212%, lymphocytes 203%, granulocytes 171%, as absolute percentage) in the maximal number of binding sites (B(max)) in all three patient samples, compared with healthy controls was detected; on the contrary, the values of the dissociation constant (K(d)) at equilibrium do not show any statistically significant variations between the two groups. These data further confirm the presence of peripheral biochemical alterations in migraine without aura. As peripheral benzodiazepine receptors appear to be involved in the regulation of the mitochondrial respiratory chain, the observed increase in B(max) might be related to the mitochondrial anomalies found in migraine disorders.

Adult↗
PubMed1998

A simple method for the quantitative description of sleep microstructure.

A simple method for the quantitative description of sleep microstructure is proposed. This method is based on the computation of descriptors which provide a normalized measure of how the amplitude of the activity in a frequency band differs, at a given instant, from its background. The use of these descriptors makes it possible to identify epochs of transient increase in band activity, to measure their length, and to measure the time distance between two successive epochs.

Adult↗
PubMed1998

Evaluation of acute ischemic stroke using quantitative EEG: a comparison with conventional EEG and CT scan.

The sensitivity of quantitative electroencephalogram (EEG) was compared with that of conventional EEG in patients with acute ischaemic stroke. In addition, a correlation between quantitative EEG data and computerized tomography (CT) scan findings was carried out for all the areas of lesion in order to reassess the actual role of EEG in the evaluation of stroke. Sixty-five patients were tested with conventional and quantitative EEG within 24 h from the onset of neurological symptoms, whereas CT scan was performed within 4 days from the onset of stroke. EEG was recorded from 19 electrodes placed upon the scalp according to the International 10-20 System. Spectral analysis was carried out on 30 artefact-free 4-sec epochs. For each channel absolute and relative power were calculated for the delta, theta, alpha and beta frequency bands and such data were successively represented in colour-coded maps. Ten patients with extensive lesions documented by CT scan were excluded. The results indicated that conventional EEG revealed abnormalities in 40 of 55 cases, while EEG mapping showed abnormalities in 46 of 55 cases: it showed focal abnormalities in five cases and nonfocal abnormalities in one of six cases which had appeared to be normal according to visual inspection of EEG. In a further 11 cases, where the conventional EEG revealed abnormalities in one hemisphere, the quantitative EEG and maps allowed to further localize abnormal activity in a more localized way. The sensitivity of both methods was higher for frontocentral, temporal and parieto-occipital cortical-subcortical infarctions than for basal ganglia and internal capsule lesions; however, quantitative EEG was more efficient for all areas of lesion in detecting cases that had appeared normal by visual inspection and was clearly superior in revealing focal abnormalities. When we considered the electrode related to which the maximum power of the delta frequency band is recorded, a fairly close correlation was found between the localization of the maximum delta power and the position of lesions documented by CT scan for all areas of lesion excepting those located in the striatocapsular area.

Acute Disease↗
PubMed1997

A quantitative study of daytime sleepiness induced by carbamazepine and add-on vigabatrin in epileptic patients.

INTRODUCTION: The clinical relevance of daytime sleepiness associated with carbamazepine (CBZ) and vigabatrin (VGB) was objectively assessed by the multiple sleep latency test (MSLT) and nocturnal sleep recordings. MATERIAL AND METHODS: Twenty-six patients with partial epilepsy and mean monthly seizure frequency of 4, aged 18 to 48 years, receiving chronic monotherapy with CBZ and subsequent VGB addition for 2 months (14 patients), were compared with a group of healthy subjects. Subjective daytime sleepiness was complained by 13 patients on CBZ monotherapy and 9 patients during VGB add-on treatment. RESULTS: No differences in nocturnal sleep parameters, but significantly shorter daytime sleep latencies at the MSLT, were detected in CBZ-treated patients as compared with healthy controls. Addition of VGB therapy did not further enhance objective daytime sleepiness. CONCLUSION: Some sleepiness occurs in chronically CBZ-treated epileptic patients, which can be objectively measured by the MSLT, but it is not aggravated by add-on VGB.

Adolescent↗
PubMed1994

Quantitative description of EEG periodicities during stationary sleep stages.

A quantitative method was applied in order to assess variations in EEG activities during sleep. Three classes of variations were distinguished: variations connected with sleep-stage changes (class 1), higher-frequency variations described by the envelope of frequency-band activities (class 2), intermediate-frequency variations, corresponding to periods from 4 to 120 s (class 3). For each class, parameters characterizing the frequency spectra were computed. These parameters were mathematically simple and clear in their meaning, since they measured power, modulation index and mean squared frequency. A statistical comparison of the mean values of the parameters during different sleep stages evidenced a certain number of significant shifts in each of the three classes. The most important class-1 and class-2 variations were described by our parameters with high levels of significance. The results obtained for class 3 were in agreement with visual observations reported in the literature, such as the progressive increase in the interval between successive arousals from sleep onset to Stage 4 and the frequent occurrence of cyclic alternating patterns during Stage 2 epochs immediately preceding REM sleep.

Journal Article↗
PubMed1992

Emotivity, personality, and task-dependent EEG asymmetry.

In order to verify if task-dependent EEG asymmetry is related to emotivity or personality traits, the relationship between EEGraphic (EEG mapping) asymmetry, personality aspects, and emotional-affective state in 12 healthy volunteers was evaluated by means of standardized methods (SAD and CPI). Our subjects show an EEG asymmetry which is currently attributed in the literature to anxiety. In our subject the absence of anxiety and the presence of hyperthymic characteristics suggests that the different individual trends observed in various studies which have used methods similar to ours, could, at least partly, depend on interference on these variables.

Adult↗
PubMed1989

A study of the interhemispheric correlation during sleep in elderly subjects.

The interhemispheric relationship during sleep in elderly subjects was studied throughout the night by a minute-by-minute computation of two linear correlation coefficients between right and left EEG activities. One of these coefficients (X delta) related to the 1-4-Hz band activity, and the other (X sigma) to the 12.5-14.5-Hz band activity. For five of the six subjects examined, it was found that the rapid-eye-movement (REM) mean values of both coefficients were significantly different from the nonrapid-eye-movement (NREM) values. A comparison between this elderly group and a control group of young subjects, examined previously, did not reveal any significant shift, either for the REM or for the NREM mean values of the coefficients.

Aged↗
PubMedDate not supplied

Topographic variations in EEG asymmetry during sleep.

EEG signals were recorded in 11 normal subjects from F4-C4, F3-C3, P4-O2 and P3-O1 during both stage 2 and the REM stage of each NREM/REM cycle. The logarithm of the right/left ratio for the power in the range of the various frequency bands showed a prevalent right-side asymmetry only with the fronto-central derivations. This trend, observed for all frequency bands, remained stable over the various NREM/REM cycles with the exception of the last one. These data indirectly support the hypothesis that the right hemisphere is more heavily involved in dreaming than the left, and suggest a prevalent involvement of the anterior regions.

Adult↗