Jaroslaw Zygierewicz

Publications of Jaroslaw Zygierewicz

• Open database of epileptic EEG with MRI and postoperational assessment of foci--a real world verification for the EEG inverse solutions.

  Authors: Piotr Zwoliński, Marcin Roszkowski, Jaroslaw Zygierewicz, Stefan Haufe, Guido Nolte, Piotr J Durka

  Neuroinformatics. 12/2010; 8(4):285-99.

  This paper introduces a freely accessible database http://eeg.pl/epi , containing 23 datasets from patients diagnosed with and operated on for drug-resistant epilepsy. This was collected as part ofThis paper introduces a freely accessible database http://eeg.pl/epi , containing 23 datasets from patients diagnosed with and operated on for drug-resistant epilepsy. This was collected as part of the clinical routine at the Warsaw Memorial Child Hospital. Each record contains (1) pre-surgical electroencephalography (EEG) recording (10-20 system) with inter-ictal discharges marked separately by an expert, (2) a full set of magnetic resonance imaging (MRI) scans for calculations of the realistic forward models, (3) structural placement of the epileptogenic zone, recognized by electrocorticography (ECoG) and post-surgical results, plotted on pre-surgical MRI scans in transverse, sagittal and coronal projections, (4) brief clinical description of each case. The main goal of this project is evaluation of possible improvements of localization of epileptic foci from the surface EEG recordings. These datasets offer a unique possibility for evaluating different EEG inverse solutions. We present preliminary results from a subset of these cases, including comparison of different schemes for the EEG inverse solution and preprocessing. We report also a finding which relates to the selective parametrization of single waveforms by multivariate matching pursuit, which is used in the preprocessing for the inverse solutions. It seems to offer a possibility of tracing the spatial evolution of seizures in time.

• Open database of epileptic EEG with MRI and postoperational assessment of foci --- a real world verification for the EEG inverse solutions

  Authors: Piotr Zwolinski, Marcin Roszkowski, Jaroslaw Zygierewicz, Stefan Haufe, Guido Nolte, Piotr J. Durka

  Neuroinformatics. 01/2010; 8:285-299.

• Event-related desynchronization and synchronization in evoked K-complexes.

  Authors: Jaroslaw Zygierewicz, Urszula Malinowska, Piotr Suffczynski, Tadeusz Piotrowski, Piotr J Durka

  Acta neurobiologiae experimentalis. 02/2009; 69(2):254-61.

  K-complexes - phenomena occurring in sleep EEG - pose severe challenges in terms of detection as well as finding their physiological origin. In this study, K-complexes (KCs) were evoked by auditoryK-complexes - phenomena occurring in sleep EEG - pose severe challenges in terms of detection as well as finding their physiological origin. In this study, K-complexes (KCs) were evoked by auditory stimuli delivered during sleep. The use of evoked KCs enables testing the sleeping nervous system under good experimental control. This paradigm allowed us to adopt into the KC studies a method of signal analysis that provides time-frequency maps of statistically significant changes in signal energy density. Our results indicate that KCs and sleep spindles may be organized by a slow oscillation. Accordingly, KCs might be evoked only if the stimulus occurs in a certain phase of the slow oscillation. We also observed middle-latency evoked responses following auditory stimulation in the last sleep cycle. This effect was revealed only by the time-frequency maps and was not visible in standard averages.

• A model of sleep spindles generation.

  Authors: Jaroslaw Zygierewicz, Piotr Suffczynski, Katarzyna J. Blinowska

  Neurocomputing. 01/2001; 38-40:1619-1625.