Neurophysiologic Assessment of Motor Imagery Training by Using Virtual Reality for Pediatric Population with Cerebral Palsy

[ES] Existen diversas evidencias que indican que los déficits motores en los pacientes de parálisis cerebral se asocian con problemas en la planificación motora que, a su vez, apuntan a una mermada capacidad para imaginar movimientos. La imaginación motora se ha revelado como una herramienta efectiva en el aprendizaje y la adquisición de habilidades motoras ya que comparte estructuras neuronales similares con la ejecución motora. En este trabajo se presenta un paradigma basado en un juego de realidad virtual para guiar la actividad mental del paciente que sirve a dos fines: estudiar su capacidad de imaginar movimientos e implicar y motivar al paciente en el entrenamiento de dicha capacidad. El estudio ha involucrado cuatro niños con parálisis cerebral espástica (edad media = 13.25 años, DS = 1.5) con lesión cerebral bilateral. Los resultados obtenidos del análisis de su actividad electroencefalográfica muestran que estos pacientes son capaces de emplear la imaginación motora en una tarea de marcha, indicada por la presencia del fenómeno ERD (Event Related Desynchronization) en zonas corticales motoras, independientemente de su nivel funcional y de los miembros afectados.[EN] There are several evidences showing that motor disorders in patients with cerebral palsy are associated with problems in motor planning, which, in turn, denote a diminished capability to imagine movements. Motor imagery appears like an effective means in learning and  acquiring motor skills since it shares similar neural structures to those ones used in motor execution. In this paper, a paradigm based on a virtual reality game that drives the patient’s electroencephalographic signal is presented. This study aims, on the one hand, to analyze the patients’ ability of imagining movements and, on the other hand, to involve and motivate them in order to implement this ability. The research work has engaged four children with spastic cerebral palsy (mean age = 13.25, SD = 1.5) with bilateral brain damage. After analyzing their electroencephalographic signal, the results show that these patients are able of using motor imagery in a walking task, as indicated by the presence of ERD (event related desynchronization) in cortical motor areas, regardless their functional impairment and affected body extremities.Este trabajo ha sido financiado parcialmente por los proyectos CP-WALKER (DPI2012-39133-C03-01), MD (PIE201650E055) y NeuroMOD (DPI2015-68664-C4-1-R)Del Castillo, M.; Serrano, J.; Lerma, S.; Martínez, I.; Rocon, E. (2018). Evaluación Neurofisiológica del Entrenamiento de la Imaginación Motora con Realidad Virtual en Pacientes Pediátricos con Parálisis Cerebral. Revista Iberoamericana de Automática e Informática industrial. 15(2):174-179. https://doi.org/10.4995/riai.2017.8819OJS174179152Bayón, C., Ramírez, O., Serrano, J.I., del Castillo, M.D., Pérez-Somarriba, A., Belda-Lois, J.M., Martínez-Caballero, I., Lerma-Lara, S., Cifuentes, C., Frizera, A., Rocon, E., 2017. Development and evaluation of a novel robotic platform for gait rehabilitation in patients with cerebral palsy: CPWalker. Robotics and Autonomous Systems, 91, 101-114. https://doi.org/10.1016/j.robot.2016.12.015Blair, E., 2010. Epidemiology of the cerebral palsies. Orthopedic Clinics of North America, 41, 441-55. https://doi.org/10.1016/j.ocl.2010.06.004Chang, M.C., Kim, D.Y., Park, D.H., 2015. Enhancement of cortical excitability and lower limb motor function in patients with stroke by transcranial direct current stimulation. Brain Stimulation, 8(3), 561-566. https://doi.org/10.1016/j.brs.2015.01.411Crajé, C., van Elk, M., Beeren, M., van Schie, H.T., Bekkering, H., Steenbergen, B., 2010. Compromised motor planning and motor imagery in right hemiparetic cerebral palsy. Research in Developmental Disabilities, 3186, 1313-1322. https://doi.org/10.1016/j.ridd.2010.07.010Iosa, M., Zocolillo, L., Montesi, M., Morelli, D., Paolucci, S., Fusco, A., 2014. The brain's sense of walking: a study on the intertwine between locomotor imagery and internal locomotor models in healthy adults, typically developing children and children with cerebral palsy. Frontiers in Human Neuroscience, 8(359), 1-9. https://doi.org/10.3389/fnhum.2014.00859Labruyère, R., Gerber, C.N., Birrer‐Brütsch, K., Meyer‐Heim, A., van Hedel, H., 2013. Requirements for and impact of a serious game for neuro‐pediatric robot‐assisted gait training. Research in Developmental Disabilities, 34, 3906-3915. https://doi.org/10.1016/j.ridd.2013.07.031Laver, K., George, S., Thomas, S., Deutsch, JE., Crotty, M., 2012. Cochrane review: virtual reality for stroke rehabilitation. European Journal of Physical and Rehabilitation Medicine, 48(3), 523-530.Lerma, S., del Castillo, M.D., Serrano, J.I., Rocon, E., Raya, R., Martínez, I., 2015. EEG control of gait in children with cerebral palsy. Preliminary data for the construction of a brain computer interface. Gait & Posture 42, S42. https://doi.org/10.1016/j.gaitpost.2015.06.082Meyer-Heim, A., van Hedel, HJA., 2013. Robot-assisted and computer-enhanced therapies for children with cerebral palsy: current state and slinical implementation. Seminars in Pediatric Neurology, 02, 139-145. https://doi.org/10.1016/j.spen.2013.06.006Mullen, T., Kothe, C., Chi, Y.M., Ojeda, A., Kerth, T., Makeig, S., Cauwenberghs, G., Jung, T.-P., 2013. Real-time modeling and 3d visualization of source dynamics and connectivity using wearable EEG. In Procceedings of IEEE EMBS, 2013, pp. 2184-2187.Mutsaarts, M., Steenbergen, B., Bekkering, H., 2007. Impaired motor imagery in right hemiparetic cerebral palsy. Experimental Brain Research, 172, 151-162. https://doi.org/10.1007/s00221-005-0327-0Niazi, I.K., Mrachacz-Kersting, N., Jiang, N., Dremstrup, K., Farina, D., 2012. Peripheral electrical stimulation triggered by self-paced detection of motor intention enhances motor evoked potentials. IEEE Transactions on Neural Systems and Rehabilitation Engineering, 20(4), 595-604. https://doi.org/10.1109/TNSRE.2012.2194309Pfurtscheller, G., da Silva, F. H. L. 1999. Event-related EEG/EMG synchronization and desynchronization: basic principles, Clinical Neurophysiology, 110, 1842-1857. https://doi.org/10.1016/S1388-2457(99)00141-8Ridderinkhof, KR., Brass, M., 2015. How kinesthetic motor Imagery works: a predictive-processing theory of visualization in sports and motor expertise. Journal of Physiology, 109, 35-63. https://doi.org/10.1016/j.jphysparis.2015.02.003Rose, FD., Brooks, BM., Rizzo A., 2005. Virtual reality in brain damage rehabilitation: review. Cyberpsychology Behavior, 8(3), 241-62. https://doi.org/10.1089/cpb.2005.8.241Sharma, N., Baron, JC., 2013. Does motor imagery share neural networks with executed movement: a multivariate fMRI analysis. Frontiers in Human Neuroscience, 7:564. https://doi.org/10.3389/fnhum.2013.00564Shin, Y.K., Lee, D.R., Hwang, H.J., You, S.J., Im, C.H., 2012. A novel EEG-based brain mapping to determine cortical activation patterns in normal children and children with cerebral palsy during motor imagery tasks. Neurorehabilitation, 31(4), 349-355. DOI: 10.3233/NRE-2012-00803Spruijt, S., ven der Kamp, J., Steenbergen, B., 2015. Current insights in the development of children's motor imagery ability. Research in Developmental Disabilities, 34, 4154-60. https://doi.org/10.1016/j.ridd.2013.08.044Weiss, P.L., Keshner, EA., Levin, M.F. (eds.), 2014. Virtual Reality for Physical and Motor Rehabilitation, Springer. https://doi.org/10.1007/978-1-4939-0968-1Winkler, I., Haufe, S., Tangermann, M., 2011. Automatic classification of artifactual ICA-Components for artifact removal in EEG signals. Behavioral and Brain Functions, 7(30), 1-15. https://doi.org/10.1186/1744-9081-7-30You, S.H., Jang, S.H., Kim, Y.H., Hallett, M., Ahn, S.H., Kwon, Y.H., Kim, J.H, Lee, M.Y., 2005. Virtual reality-induced cortical reorganization and associated locomotor recovery in chronic stroke: an experimenter-blind randomized study. Stroke, 36(6), 1166-1171. https://doi.org/10.1161/01.STR.0000162715.43417.9

The exposure of the hybrid detector of the Pierre Auger Observatory

The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The "hybrid" detection mode combines the information from the two subsystems. We describe the determination of the hybrid exposure for events observed by the fluorescence telescopes in coincidence with at least one water-Cherenkov detector of the surface array. A detailed knowledge of the time dependence of the detection operations is crucial for an accurate evaluation of the exposure. We discuss the relevance of monitoring data collected during operations, such as the status of the fluorescence detector, background light and atmospheric conditions, that are used in both simulation and reconstruction.Comment: Paper accepted by Astroparticle Physic

Model-independent search for CP violation in D0→K−K+π−π+ and D0→π−π+π+π− decays

A search for CP violation in the phase-space structures of D0 and View the MathML source decays to the final states K−K+π−π+ and π−π+π+π− is presented. The search is carried out with a data set corresponding to an integrated luminosity of 1.0 fb−1 collected in 2011 by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. For the K−K+π−π+ final state, the four-body phase space is divided into 32 bins, each bin with approximately 1800 decays. The p-value under the hypothesis of no CP violation is 9.1%, and in no bin is a CP asymmetry greater than 6.5% observed. The phase space of the π−π+π+π− final state is partitioned into 128 bins, each bin with approximately 2500 decays. The p-value under the hypothesis of no CP violation is 41%, and in no bin is a CP asymmetry greater than 5.5% observed. All results are consistent with the hypothesis of no CP violation at the current sensitivity

Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum

We report a first measurement for ultra-high energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers registered simultaneously by the fluorescence and the surface detectors of the Pierre Auger Observatory. Such a correlation measurement is a unique feature of a hybrid air-shower observatory with sensitivity to both the electromagnetic and muonic components. It allows an accurate determination of the spread of primary masses in the cosmic-ray flux. Up till now, constraints on the spread of primary masses have been dominated by systematic uncertainties. The present correlation measurement is not affected by systematics in the measurement of the depth of shower maximum or the signal in the water Cherenkov stations. The analysis relies on general characteristics of air showers and is thus robust also with respect to uncertainties in hadronic event generators. The observed correlation in the energy range around the `ankle' at $\lg(E/{\rm eV})=18.5-19.0$ differs significantly from expectations for pure primary cosmic-ray compositions. A light composition made up of proton and helium only is equally inconsistent with observations. The data are explained well by a mixed composition including nuclei with mass $A > 4$. Scenarios such as the proton dip model, with almost pure compositions, are thus disfavoured as the sole explanation of the ultrahigh-energy cosmic-ray flux at Earth.Comment: Published version. Added journal reference and DOI. Added Report Numbe

Search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓

A search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓ is performed with a data sample, corresponding to an integrated luminosity of 1.0  fb-1 of pp collisions at √s=7  TeV, collected by the LHCb experiment. The observed number of Bs0→e±μ∓ and B0→e±μ∓ candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be B(Bs0→e±μ∓)101  TeV/c2 and MLQ(B0→e±μ∓)>126  TeV/c2 at 95% C.L., and are a factor of 2 higher than the previous bounds

Study of the production of Λb0\Lambda_b^0 and B‾0\overline{B}^0 hadrons in pppp collisions and first measurement of the Λb0→J/ψpK−\Lambda_b^0\rightarrow J/\psi pK^- branching fraction

The product of the $\Lambda_b^0$ ($\overline{B}^0$) differential production cross-section and the branching fraction of the decay $\Lambda_b^0\rightarrow J/\psi pK^-$ ($\overline{B}^0\rightarrow J/\psi\overline{K}^*(892)^0$) is measured as a function of the beauty hadron transverse momentum, $p_{\rm T}$, and rapidity, $y$. The kinematic region of the measurements is $p_{\rm T}<20~{\rm GeV}/c$ and $2.0<y<4.5$. The measurements use a data sample corresponding to an integrated luminosity of $3~{\rm fb}^{-1}$ collected by the LHCb detector in $pp$ collisions at centre-of-mass energies $\sqrt{s}=7~{\rm TeV}$ in 2011 and $\sqrt{s}=8~{\rm TeV}$ in 2012. Based on previous LHCb results of the fragmentation fraction ratio, $f_{\Lambda_B^0}/f_d$, the branching fraction of the decay $\Lambda_b^0\rightarrow J/\psi pK^-$ is measured to be \begin{equation*} \mathcal{B}(\Lambda_b^0\rightarrow J/\psi pK^-)= (3.17\pm0.04\pm0.07\pm0.34^{+0.45}_{-0.28})\times10^{-4}, \end{equation*} where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay $\overline{B}^0\rightarrow J/\psi\overline{K}^*(892)^0$, and the fourth is due to the knowledge of $f_{\Lambda_b^0}/f_d$. The sum of the asymmetries in the production and decay between $\Lambda_b^0$ and $\overline{\Lambda}_b^0$ is also measured as a function of $p_{\rm T}$ and $y$. The previously published branching fraction of $\Lambda_b^0\rightarrow J/\psi p\pi^-$, relative to that of $\Lambda_b^0\rightarrow J/\psi pK^-$, is updated. The branching fractions of $\Lambda_b^0\rightarrow P_c^+(\rightarrow J/\psi p)K^-$ are determined.Comment: 29 pages, 19figures. All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-032.htm

A Historiometric Examination of Machiavellianism and a New Taxonomy of Leadership

Although researchers have extensively examined the relationship between charismatic leadership and Machiavellianism (Deluga, 2001; Gardner & Avolio, 1995; House & Howell, 1992), there has been a lack of investigation of Machiavellianism in relation to alternative forms of outstanding leadership. Thus, the purpose of this investigation was to examine the relationship between Machiavellianism and a new taxonomy of outstanding leadership comprised of charismatic, ideological, and pragmatic leaders. Using an historiometric approach, raters assessed Machiavellianism via the communications of 120 outstanding leaders in organizations across the domains of business, political, military, and religious institutions. Academic biographies were used to assess twelve general performance measures as well as twelve general controls and five communication specific controls. The results indicated that differing levels of Machiavellianism is evidenced across the differing leader types as well as differing leader orientation. Additionally, Machiavellianism appears negatively related to performance, though less so when type and orientation are taken into account.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Measurements of long-range near-side angular correlations in sNN=5\sqrt{s_{\text{NN}}}=5TeV proton-lead collisions in the forward region

Two-particle angular correlations are studied in proton-lead collisions at a nucleon-nucleon centre-of-mass energy of $\sqrt{s_{\text{NN}}}=5$TeV, collected with the LHCb detector at the LHC. The analysis is based on data recorded in two beam configurations, in which either the direction of the proton or that of the lead ion is analysed. The correlations are measured in the laboratory system as a function of relative pseudorapidity, $\Delta\eta$, and relative azimuthal angle, $\Delta\phi$, for events in different classes of event activity and for different bins of particle transverse momentum. In high-activity events a long-range correlation on the near side, $\Delta\phi \approx 0$, is observed in the pseudorapidity range $2.0<\eta<4.9$. This measurement of long-range correlations on the near side in proton-lead collisions extends previous observations into the forward region up to $\eta=4.9$. The correlation increases with growing event activity and is found to be more pronounced in the direction of the lead beam. However, the correlation in the direction of the lead and proton beams are found to be compatible when comparing events with similar absolute activity in the direction analysed.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-040.htm

Evidence for the strangeness-changing weak decay Ξb−→Λb0π−\Xi_b^-\to\Lambda_b^0\pi^-

Using a $pp$ collision data sample corresponding to an integrated luminosity of 3.0~fb$^{-1}$, collected by the LHCb detector, we present the first search for the strangeness-changing weak decay $\Xi_b^-\to\Lambda_b^0\pi^-$. No $b$ hadron decay of this type has been seen before. A signal for this decay, corresponding to a significance of 3.2 standard deviations, is reported. The relative rate is measured to be ${{f_{\Xi_b^-}}\over{f_{\Lambda_b^0}}}{\cal{B}}(\Xi_b^-\to\Lambda_b^0\pi^-) = (5.7\pm1.8^{+0.8}_{-0.9})\times10^{-4}$, where $f_{\Xi_b^-}$ and $f_{\Lambda_b^0}$ are the $b\to\Xi_b^-$ and $b\to\Lambda_b^0$ fragmentation fractions, and ${\cal{B}}(\Xi_b^-\to\Lambda_b^0\pi^-)$ is the branching fraction. Assuming $f_{\Xi_b^-}/f_{\Lambda_b^0}$ is bounded between 0.1 and 0.3, the branching fraction ${\cal{B}}(\Xi_b^-\to\Lambda_b^0\pi^-)$ would lie in the range from $(0.57\pm0.21)\%$ to $(0.19\pm0.07)\%$.Comment: 7 pages, 2 figures, All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-047.htm

BB flavour tagging using charm decays at the LHCb experiment

An algorithm is described for tagging the flavour content at production of neutral $B$ mesons in the LHCb experiment. The algorithm exploits the correlation of the flavour of a $B$ meson with the charge of a reconstructed secondary charm hadron from the decay of the other $b$ hadron produced in the proton-proton collision. Charm hadron candidates are identified in a number of fully or partially reconstructed Cabibbo-favoured decay modes. The algorithm is calibrated on the self-tagged decay modes $B^+ \to J/\psi \, K^+$ and $B^0 \to J/\psi \, K^{*0}$ using $3.0\mathrm{\,fb}^{-1}$ of data collected by the LHCb experiment at $pp$ centre-of-mass energies of $7\mathrm{\,TeV}$ and $8\mathrm{\,TeV}$. Its tagging power on these samples of $B \to J/\psi \, X$ decays is $(0.30 \pm 0.01 \pm 0.01) \%$.Comment: All figures and tables, along with any supplementary material and additional information, are available at http://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-027.htm