121 research outputs found

    Mapping the Effect of Interictal Epileptic Activity Density During Wakefulness on Brain Functioning in Focal Childhood Epilepsies With Centrotemporal Spikes

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    Childhood epilepsy with centrotemporal spikes (CECTS) is the most common type of \u201cself-limited focal epilepsies.\u201d In its typical presentation, CECTS is a condition reflecting non-lesional cortical hyperexcitability of rolandic regions. The benign evolution of this disorder is challenged by the frequent observation of associated neuropsychological deficits and behavioral impairment. The abundance (or frequency) of interictal centrotemporal spikes (CTS) in CECTS is considered a risk factor for deficits in cognition. Herein, we captured the hemodynamic changes triggered by the CTS density measure (i.e., the number of CTS for time bin) obtained in a cohort of CECTS, studied by means of video electroencephalophy/functional MRI during quite wakefulness. We aim to demonstrate a direct influence of the diurnal CTS frequency on epileptogenic and cognitive networks of children with CECTS. A total number of 8,950 CTS (range between 27 and 801) were recorded in 23 CECTS (21 male), with a mean number of 255 CTS/patient and a mean density of CTS/30 s equal to 10,866 \ub1 11.46. Two independent general linear model models were created for each patient based on the effect of interest: \u201cindividual CTS\u201d in model 1 and \u201cCTS density\u201d in model 2. Hemodynamic correlates of CTS density revealed the involvement of a widespread cortical\u2013subcortical network encompassing the sensory-motor cortex, the Broca's area, the premotor cortex, the thalamus, the putamen, and red nucleus, while in the CTS event-related model, changes were limited to blood\u2013oxygen-level-dependent (BOLD) signal increases in the sensory-motor cortices. A linear relationship was observed between the CTS density hemodynamic changes and both disease duration (positive correlation) and age (negative correlation) within the language network and the bilateral insular cortices. Our results strongly support the critical role of the CTS frequency, even during wakefulness, to interfere with the normal functioning of language brain networks

    fMRI-Based Effective Connectivity in Surgical Remediable Epilepsies: A Pilot Study

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    Simultaneous EEG-fMRI can contribute to identify the epileptogenic zone (EZ) in focal epilepsies. However, fMRI maps related to Interictal Epileptiform Discharges (IED) commonly show multiple regions of signal change rather than focal ones. Dynamic causal modeling (DCM) can estimate effective connectivity, i.e. the causal effects exerted by one brain region over another, based on fMRI data. Here, we employed DCM on fMRI data in 10 focal epilepsy patients with multiple IED-related regions of BOLD signal change, to test whether this approach can help the localization process of EZ. For each subject, a family of competing deterministic, plausible DCM models were constructed using IED as autonomous input at each node, one at time. The DCM findings were compared to the presurgical evaluation results and classified as: "Concordant" if the node identified by DCM matches the presumed focus, "Discordant" if the node is distant from the presumed focus, or "Inconclusive" (no statistically significant result). Furthermore, patients who subsequently underwent intracranial EEG recordings or surgery were considered as having an independent validation of DCM results. The effective connectivity focus identified using DCM was Concordant in 7 patients, Discordant in two cases and Inconclusive in one. In four of the 6 patients operated, the DCM findings were validated. Notably, the two Discordant and Invalidated results were found in patients with poor surgical outcome. Our findings provide preliminary evidence to support the applicability of DCM on fMRI data to investigate the epileptic networks in focal epilepsy and, particularly, to identify the EZ in complex cases

    Mapping the Effect of Interictal Epileptic Activity Density During Wakefulness on Brain Functioning in Focal Childhood Epilepsies With Centrotemporal Spikes

    Get PDF
    Childhood epilepsy with centrotemporal spikes (CECTS) is the most common type of \u201cself-limited focal epilepsies.\u201d In its typical presentation, CECTS is a condition reflecting non-lesional cortical hyperexcitability of rolandic regions. The benign evolution of this disorder is challenged by the frequent observation of associated neuropsychological deficits and behavioral impairment. The abundance (or frequency) of interictal centrotemporal spikes (CTS) in CECTS is considered a risk factor for deficits in cognition. Herein, we captured the hemodynamic changes triggered by the CTS density measure (i.e., the number of CTS for time bin) obtained in a cohort of CECTS, studied by means of video electroencephalophy/functional MRI during quite wakefulness. We aim to demonstrate a direct influence of the diurnal CTS frequency on epileptogenic and cognitive networks of children with CECTS. A total number of 8,950 CTS (range between 27 and 801) were recorded in 23 CECTS (21 male), with a mean number of 255 CTS/patient and a mean density of CTS/30 s equal to 10,866 \ub1 11.46. Two independent general linear model models were created for each patient based on the effect of interest: \u201cindividual CTS\u201d in model 1 and \u201cCTS density\u201d in model 2. Hemodynamic correlates of CTS density revealed the involvement of a widespread cortical\u2013subcortical network encompassing the sensory-motor cortex, the Broca's area, the premotor cortex, the thalamus, the putamen, and red nucleus, while in the CTS event-related model, changes were limited to blood\u2013oxygen-level-dependent (BOLD) signal increases in the sensory-motor cortices. A linear relationship was observed between the CTS density hemodynamic changes and both disease duration (positive correlation) and age (negative correlation) within the language network and the bilateral insular cortices. Our results strongly support the critical role of the CTS frequency, even during wakefulness, to interfere with the normal functioning of language brain networks

    Listening to a conversation with aggressive content expands the interpersonal space

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    The distance individuals maintain between themselves and others can be defined as ‘interpersonal space’. This distance can be modulated both by situational factors and individual characteristics. Here we investigated the influence that the interpretation of other people interaction, in which one is not directly involved, may have on a person’s interpersonal space. In the current study we measured, for the first time, whether the size of interpersonal space changes after listening to other people conversations with neutral or aggressive content. The results showed that the interpersonal space expands after listening to a conversation with aggressive content relative to a conversation with a neutral content. This finding suggests that participants tend to distance themselves from an aggressive confrontation even if they are not involved in it. These results are in line with the view of the interpersonal space as a safety zone surrounding one’s body

    WA92: a fixed target experiment to trigger on and identify beauty particle decays

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    We describe the detectors and trigger system used in the CERN WA92 experiment. The experiment was designed to study the production and decay of beauty particles from 350 GeV/cc\, π\,\pi^- interactions in copper and tungsten targets. Charged particle tracking is performed using the Omega spectrometer. Silicon microstrip detectors are used to provide precise tracking information in the region of the production and the decay of heavy-flavoured particles and to trigger on the resulting high impact parameter tracks. The precision of vertex reconstruction corresponds to ±3.7%\pm 3.7\% of the mean B-decay proper lifetime. Lepton and high transverse momentum hadron signals are also used in the trigger, which accepts 29\% of B-decays and rejects 98\% of non-beauty interactions

    Measurement of the beauty production cross-section in 350 GeV/c π\pi^- -Cu interactions

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    Using a sample of 10810^8 triggered events, produced in π\pi^---\,Cu interactions at 350~GeV/c/c, we have identified 26 beauty events. The estimated background in this sample is 0.6±0.60.6 \pm 0.6 events. From these data, assuming a linear A-dependence, we measure a beauty production cross-section integrated over all xFx_F of 5.7+1.31.1 (stat.)+0.60.5 (syst.) 5.7 {+1.3 \atop -1.1}~{\mathrm {(stat.)}} {+0.6 \atop -0.5}~{\mathrm {(syst.)}}~nb/N

    A study of the reaction pim p --> omega pim p at 18 GeV/c: The D and S decay amplitudes for b1(1235) --> omega pi

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    The reaction pim p --> omega pim p, omega --> pip pim pi0 has been studied at 18 GeV/c. The omega pim mass spectrum is found to be dominated by the b1(1235). Partial Wave Analysis shows that b1 production is dominated by natural parity exchange. The S-wave and D-wave amplitudes for b1(1235) --> omega pi have been determined, and it is found that the amplitude ratio, |D/S| = 0.269 +/- (0.009)stat +/- (0.01)sys and the phase difference, phi(D-S) = 10.54 deg +/- (2.4)stat +/- (3.9)sys.Comment: 7 pages, 9 figures, revtex4 format, to be published in Physics Letters
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