• Measure profile surrogates: a method to validate the performance of epileptic seizure prediction algorithms

  Kreuz, Thomas; Andrzejak, Ralph Gregor; Mormann, Florian; Kraskov, Alexander; Stögbauer, Harald; Elger, Christian E.; Lehnertz, Klaus; Grassberger, Peter (American Physical Society, 2004)

  In a growing number of publications it is claimed that epileptic seizures can be predicted by analyzing the electroencephalogram (EEG) with different characterizing measures. However, many of these studies suffer from a ...
• Improved statistical test for nonstationarity using recurrence time statistics

  Rieke, Christoph; Andrzejak, Ralph Gregor; Mormann, Florian; Lehnertz, Klaus (American Physical Society, 2003)

  We have recently introduced a measure for nonstationarity using a recurrence time statistic to assess stationarity. In this paper we propose an extension of this method based on a detailed study of the statistics for ...
• Detection of weak directional coupling: phase-dynamics approach versus state-space approach

  Smirnov, Dmitry A.; Andrzejak, Ralph Gregor (American Physical Society, 2005)

  We compare two conceptually different approaches to the detection of weak directional couplings between two oscillatory systems from bivariate time series. The first approach is based on the analysis of the systems’ phase ...
• Independent delta/theta rhythms in the human hippocampus and entorhinal cortex

  Mormann, Florian; Osterhage, Hannes; Andrzejak, Ralph Gregor; Weber, Bernd; Fernández, Guillén; Fell, Juerguen; Elger, Christian E.; Lehnertz, Klaus (Frontiers, 2008)

  Theta oscillations in the medial temporal lobe (MTL) of mammals are involved in various functions such as spatial navigation, sensorimotor integration, and cognitive processing. While the theta rhythm was originally assumed ...
• Using bivariate signal analysis to characterize the epileptic focus: the benefit of surrogates

  Andrzejak, Ralph Gregor; Chicharro Raventós, Daniel; Lehnertz, Klaus; Mormann, Florian (American Physical Society, 2011)

  The disease epilepsy is related to hypersynchronous activity of networks of neurons. While acute epileptic seizures are the most extreme manifestation of this hypersynchronous activity, an elevated level of interdependence ...
• On the spectral formulation of Granger causality

  Chicharro Raventós, Daniel (Springer, 2011)

  Spectral measures of causality are used to explore the role of different rhythms in the causal connectivity between brain regions. We study several spectral measures related to Granger causality, comprising the bivariate ...
• Nonrandomness, nonlinear dependence, and nonstationarity of electroencephalographic recordings from epilepsy patients

  Andrzejak, Ralph Gregor; Schindler, Kaspar A.; Rummel, Christian (American Physiological Society, 2012)

  To derive tests for randomness, nonlinear-independence, and stationarity, we combine surrogates with a nonlinear prediction error, a nonlinear interdependence measure, and linear variability measures, respectively. We apply ...
• Methodological advances in brain connectivity

  Faes, Luca; Andrzejak, Ralph Gregor; Ding, Mingzhou; Kugiumtzis, Dimitris (Hindawi, 2012)

  Determining how distinct neurons or brain regions are connected and communicate with each other is a crucial point in neuroscience, as it allows to investigate how the functional integration of specialized neural populations ...
• Detecting determinism from point processes

  Andrzejak, Ralph Gregor; Mormann, Florian; Kreuz, Thomas (American Physical Society, 2014)

  The detection of a nonrandom structure from experimental data can be crucial for the classification, understanding, and interpretation of the generating process. We here introduce a rank-based nonlinear predictability ...
• Gamut reduction through local saturation reduction

  Zamir, Syed Waqas; Vazquez-Corral, Javier; Bertalmío, Marcelo (Society for Imaging Science and Technology, 2017)
• Gamut mapping for visual attention retargeting

  Vazquez-Corral, Javier; Bertalmío, Marcelo (Society for Imaging Science and Technology, 2017)

  Visual attention retargeting attempts to modify an image such that the viewer’s attention is directed to specific regions. Goals include highlighting a particular object or hiding possible problems in the image. In this ...
• Atrial functional and geometrical remodeling in highly trained male athletes: for better or worse?

  Gabrielli, Luigi; Bijnens, Bart; Butakoff, Constantine; Duchateau, Nicolas; Montserrat, Silvia; Merino, Beatriz; Gutierrez, Josep; Paré, Carles; Mont, Lluís; Brugada, Josep; Sitges, Marta (Springer, 2014)

  Purpose Highly trained athletes have an increased risk of atrial arrhythmias. Atrial geometrical and functional remodeling may be the underlying substrate. We analyze and relate atrial size, deformation and performance ...
• Interatrial dyssynchrony may contribute to heart failure symptoms in patients with preserved ejection fraction

  Sanchis, Laura; Vannini, Luca; Gabrielli, Luigi; Duchateau, Nicolas; Falces, Carles; Andrea, Rut; Bijnens, Bart; Sitges, Marta (Wiley, 2015)

  Purpose Heart failure (HF) with preserved ejection fraction (HFPEF) is the most prevalent type of HF in nonhospitalized patients, but its pathophysiology remains poorly understood. The aim of our study was to assess the ...
• Co-creating a web-based visual representation model for authoring blended learning designs

  Albó, Laia; Hernández Leo, Davinia (Scuola IaD, 2019)

  This paper reports the co-creation process carried out during the development of a web-based visual representation model for authoring blended learning designs. The results of several participatory design workshops with ...
• Analysis of UAV communications in cell-free massive MIMO systems

  D’Andrea, Carmen; García Rodríguez, Adrián; Geraci, Giovanni; Galati Giordano, Lorenzo; Buzzi, Stefano (Institute of Electrical and Electronics Engineers (IEEE), 2020)

  We study support for unmanned aerial vehicle (UAV) communications through a cell-freemassive MIMO architecture, wherein a large number of access points (APs) is deployed in place of largeco-located massive MIMO arrays. We ...
• Learned effects of structural components of newscasts on viewers’ information processing: The case of Stings

  Barreda Ángeles, Miguel; Pereda-Baños, Alexandre; Ferràndiz Bofill, Xavier; Costa, Albert, 1970- (De Gruyter, 2017)

  This article proposes that syntactic features of newscasts can act as learned motivational stimuli determining both viewers’ attention and memory for information. An experiment was conducted in which we manipulated the ...
• Vision models for wide color gamut imaging in cinema

  Zamir, Syed Waqas; Vazquez-Corral, Javier; Bertalmío, Marcelo (Institute of Electrical and Electronics Engineers (IEEE), 2019)

  Gamut mapping is the problem of transforming the colors of image or video content so as to fully exploit the color palette ofthe display device where the content will be shown, while preserving the artistic intent of the ...
• A Fluctuation-driven mechanism for slow decision processes in reverberant networks

  Martí, Daniel; Deco, Gustavo; Mattia, Maurizio; Gigante, Guido; Del Giudice, Paolo (Public Library of Science (PLoS), 2008)

  The spike activity of cells in some cortical areas has been found to be correlated with reaction times and behavioral responses during two-choice decision tasks. These experimental findings have motivated the study of ...
• Conceptualising a visual representation model for MOOC-based blended learning designs

  Albó, Laia; Hernández Leo, Davinia (2020)

  This article reports on a study about how massive open online course (MOOC)-based blended learning designs can be visually represented to facilitate their comprehension and sharing. We carried out an iterative co-creation ...
• Thermal impact of balloon occlusion of the coronary sinus during mitral isthmus radiofrequency ablation: an in-silico study

  González-Suárez, Ana; d'Avila, Andre; Pérez, Juan J.; Reddy, Vivek Y.; Camara, Oscar; Berjano, Enrique J. (Taylor & Francis, 2019)

  Purpose: Although experimental data have suggested that temporary occlusion of the coronary sinus (CS) can facilitate the creation of transmural lesions across the atrial wall (AW) during mitral isthmus radiofrequency ...

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