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Gert Pfurtscheller

Other affiliations: University of Graz
Bio: Gert Pfurtscheller is an academic researcher from Graz University of Technology. The author has contributed to research in topics: Brain–computer interface & Electroencephalography. The author has an hindex of 117, co-authored 507 publications receiving 62873 citations. Previous affiliations of Gert Pfurtscheller include University of Graz.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the spatial distribution of a post-movement beta ERS can be visualized by computing the local average reference (LAR) method and the linear estimation (LE) method can also be applied to study the spatiotemporal ERS patterns.
Abstract: Event-related desynchronization (ERS) describes a short-lasting and localized amplitude enhancement of specific frequency components. The spatial distribution of a post-movement beta ERS can be visualized by computing the local average reference (LAR). The Linear estimation (LE) method can also be applied to study the spatiotemporal ERS patterns. As source space an hemisphere was used with equally distributed radially oriented current dipoles. The lead field matrix is normalized to make sure that all dipoles have the same average impact on the sensors. A distributed source solution is found for each timestep and for each trial. Event-related Desynchronization calculations are carried out for every dipole (squaring of amplitude, averaging over all trials and time averaging over 16 time points). Both methods were conducted for the study of voluntary hand movement. The results are similar but in contrast to the LAR maps, the LE maps show a better spatial resolution. This is not surprising since the LAR method is limited to the electrode sites whereas with LE the EEG activity is projected onto the source space. Furthermore, the LE method counteracts the deblurring caused by the poorly conducting skull. Linear Estimation depends on several assumptions about the source space, volume conductor and the regularization parameter. Further investigation is needed to evaluate the application of LE for the study of Event-Related EEG phenomena.

14 citations

Book ChapterDOI
TL;DR: This chapter discusses changes in central electroencephalography (EEG) activity in relation to voluntary movement and introduces the results of a study on 20 normal subjects of the behaviour of central mu activity and negative potential shift preceding and during voluntary pressing of a rubber ball.
Abstract: Publisher Summary This chapter discusses changes in central electroencephalography (EEG) activity in relation to voluntary movement. In the central region various changes in the EEG activity can be recorded before and during a self-paced voluntary movement. These changes can be found either in the intrinsic EEG and here especially in the rhythmic activity within the alpha band in form of a movement-related amplitude reduction (desynchronization) or in the slow negative potential shift known as Bereitschaftspotential. Beside this, different macropotentials—for example, the motor cortex potential, are also generated. The chapter introduces the results of a study on 20 normal subjects, of the behaviour of central mu activity and negative potential shift preceding and during voluntary pressing of a rubber ball. The reason for the use of a rubber ball, of about 5 cm diameter, for the execution of a voluntary movement is that the same ball is to be used also in a study on patients with cerebral hemispheric lesions (expansive or infarct).

14 citations

21 Sep 2005
TL;DR: In this article, a brain-computer interface (BCI) is used to transform thought-modulated EEG signals into an output signal that controls events within a virtual environment (VE).
Abstract: Able-bodied participants are able to move forward in a Virtual Environment (VE) by imagining movements of their feet. This is achieved by exploiting a Brain-Computer Interface (BCI) which transforms thought-modulated EEG signals into an output signal that controls events within the VE. The experiments were carried out in an immersive projection environment, commonly referred to as a "Cave” in which participants were able to move through a virtual street by foot imagery alone. Experiments of BCI feedback on a normal monitor, VE experiments with a head-mounted display (HMD) and in the Cave-VE are compared.

14 citations

Journal ArticleDOI
TL;DR: An asynchronous SSVEP-BCI, based on canonical correlation analysis, suitable for the control of a 2-degrees of freedom (DoF) hand and elbow neuroprosthesis is realization.
Abstract: A brain-computer interface (BCI) provides a direct connection between the human brain and a computer. One type of BCI can be realized using steady-state visual evoked potentials (SSVEPs), resulting from repetitive stimulation. The aim of this study was the realization of an asynchronous SSVEP-BCI, based on canonical correlation analysis, suitable for the control of a 2-degrees of freedom (DoF) hand and elbow neuroprosthesis. To determine whether this BCI is suitable for the control of 2-DoF neuroprosthetic devices, online experiments with a virtual and a robotic limb feedback were conducted with eight healthy subjects and one tetraplegic patient. All participants were able to control the artificial limbs with the BCI. In the online experiments, the positive predictive value (PPV) varied between 69% and 83% and the false negative rate (FNR) varied between 1% and 17%. The spinal cord injured patient achieved PPV and FNR values within one standard deviation of the mean for all healthy subjects.

14 citations


Cited by
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Journal ArticleDOI
TL;DR: EELAB as mentioned in this paper is a toolbox and graphic user interface for processing collections of single-trial and/or averaged EEG data of any number of channels, including EEG data, channel and event information importing, data visualization (scrolling, scalp map and dipole model plotting, plus multi-trial ERP-image plots), preprocessing (including artifact rejection, filtering, epoch selection, and averaging), Independent Component Analysis (ICA) and time/frequency decomposition including channel and component cross-coherence supported by bootstrap statistical methods based on data resampling.

17,362 citations

Journal Article
TL;DR: This book by a teacher of statistics (as well as a consultant for "experimenters") is a comprehensive study of the philosophical background for the statistical design of experiment.
Abstract: THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

13,333 citations

Journal ArticleDOI
06 Jun 1986-JAMA
TL;DR: The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or her own research.
Abstract: I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

7,563 citations

Journal ArticleDOI
TL;DR: With adequate recognition and effective engagement of all issues, BCI systems could eventually provide an important new communication and control option for those with motor disabilities and might also give those without disabilities a supplementary control channel or a control channel useful in special circumstances.

6,803 citations