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Analiza porównawcza reakcji na bodźce wzrokowe i słuchowe w badaniach potencjałów wywołanych EEG

Tyburcy Łukasz, Plechawska-Wójcik Małgorzata

Journal of Computer Sciences Institute

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2018

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Vol. 7

172--177

PL

Artykuł opisuje badania polegające na porównaniu czasów reakcji na bodźce wzrokowe i słuchowe przy pomocy potencjałów wywołanych EEG. Do realizacji badań wykorzystano dwa eksperymenty. Pierwszy badał czasy reakcji na bodźce wzrokowe, drugi badał czasy reakcji na bodźce słuchowe. Po przeprowadzeniu analizy danych uzyskane rezultaty pozwoliły określić, że bodźce wzrokowe wywołują szybszą reakcję niż bodźce słuchowe.

EN

The paper describes results of comparison of reactions times to visual and auditory stimuli using EEG evoked potentials. Two experiments were used to applied. The first one explored reaction times to visual stimulus and the second one to auditory stimulus. After conducting an analysis of data, received results enable determining that visual stimuli evoke faster reactions than auditory stimuli.

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EEG with a reduced number of electrodes: Where to detect and how to improve visually, auditory and somatosensory evoked potentials

Stehlin S. A. F., Nguyen X. P., Niemz M. H.

Biocybernetics and Biomedical Engineering

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2018

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Vol. 38, no. 3

700--707

EN

The measurement of evoked potentials has become a standard tool to test new hardware and software for electroencephalography (EEG). In this study, we investigate where to detect and how to improve visually, auditory and somatosensory evoked potentials with a reduced number of electrodes. We measured a total of 50 evoked potentials in healthy subjects, and we were able to detect visually, auditory and somatosensory evoked potentials with just three electrodes. We also investigated where to measure a combination of visually, auditory and somatosensory evoked potentials and found the best positions to be Oz, O1, O2, TP9 and TP10. In the second part of this study, we analyzed how the evoked potentials depend on the segmentation frequency selected to superpose EEG responses. We found that the detection of visually evoked potentials requires the segmentation frequency to match the stimulus frequency with an accuracy of at least 99.92 percent. The detection of auditory evoked potentials and somatosensory evoked potentials requires a matching of at least 99.95 percent. Therefore, a correct matching of the segmentation frequency with the stimulation frequency is the primary key to improving the quality of evoked potentials.

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Entry level EEG amplifier dedicated for P300 evoked potentials measurements

Bartnik J., Rak R.

Przegląd Elektrotechniczny

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2010

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R. 86, nr 1

178-179

EN

Project of an entry level EEG amplifier dedicated for P300 evoked potentials measurements will be discussed. Amplifier main application is wireless communication between brain and a PC (BCI) which would allow locked-state people to communicate. The device should be mobile, energy efficient and inexpensive.

PL

W artykule przedstawiono projekt ekonomicznego wzmacniacza EEG z przeznaczeniem do pomiaru potencjałów wywołanych - P300. Głównym zastosowaniem wzmacniacza jest bezprzewodowa komunikacja mózg-komputer, która umożliwiłaby osobom całkowicie sparaliżowanym na porozumiewanie się. Urządzenie powinno być mobilne, energooszczędne i tanie.

4

Impossible becomes possible - the Nikolet Viking IV usage in Intra-Operative Monitoring

Rauszer A., Doleżych H.

Journal of Medical Informatics & Technologies

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2007

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Vol. 11

329--333

EN

Recent advances in surgical technology have encouraged many surgeons to explore new ways of helping patients, potentially increasing the risk to the patient's neurological system. A complication of surgery, especially neurosurgery, is the development of a post-operative neurological deficit. The original purpose for the use of various neurophysiological monitoring procedures was to reduce the incidence of neurological deficit, regardless of its origin. VIASYS Healthcare (Nicolet Biomedical) has created Nicolet Viking IV that fulfils all criteria of a good intra-operative monitoring instrument. Viking IV can perform routine and computer-aided Electromyography, Evoked Potentials Studies, Nerve Conduction Studies and Intra-Operative Monitoring. Nicolet Viking IV is also very useful in other branches of medicine like: neurology, internal medicine, obstetrics and gynaecology, neonatology and many more. Today we use intra-operating monitoring for several additional purposes, including improving overall surgical outcomes, monitoring the efficacy of intervention strategies and monitoring neurological structures that are at risk due to secondary/perisurgical variables. Intra-operative neurophysiologic monitoring (IONM) allows the detection of neurological compromise early enough that permanent deficits may be avoided.

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Development of Visual Evoked Potentials Detection AIgorithm for objective perimetry

Drozd M., Nowakowski A.

Biocybernetics and Biomedical Engineering

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2005

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Vol. 25, no. 3

47-55

EN

Objective perimetry, based on the EEG signal analysis, represents a new trend in evaluation of the human visual system. At the moment, the work is concentrated on the effective algorithms of the EEG analysis for the weak transient VEP signal detection. A new algorithm for a rapid detection of visual cortical signals - the VEPDA - was developed. For evaluation of the algorithm, two approaches are considered. The first one, based on synthetic cortical potentials and artificial, spontaneous EEG, with all data generated in the developed model, and the second one, using the real EEG data taken from measurements and mixed with the synthetic VEP signal. The approach presented in this paper concerns application of VEPDA to the modelled VEP embedded in the real, ongoing EEG signal. The final step of the work is practical implementation of the method. The research results prove the validity of the algorithm applied to the modelled data. Here, the value of VEPDA usefulness in the analysis of the real EEG recording has been verified.

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Komunikacja człowieka z komputerem za pomocą sygnału EEG

Byczuk M., Materka A.

Elektronika : prace naukowe

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2003

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nr 8

35-52

PL

Praca zawiera przegląd technik analizy sygnału EEG (elektro-encefalograficznego) stosowanych do komunikacji człowieka z komputerem i wybranych systemów wykorzystujących te techniki. Opisano w niej również autorski prototypowy system akwizycji sygnału EEG, przeznaczony do prowadzenia badań naukowych w zakresie rozwoju metod analizy tego sygnału do zastosowań w interfejsach BCI (brain-computer interface). Omówiono schemat blokowy skonstruowanego układu i obwody kompensacji zakłóceń. Przedstawiono wyniki pierwszych eksperymentów przeprowadzonych z użyciem układu prototypowego, potwierdzające jego przydatność do cyfrowej analizy sygnałów EEG, w środowisku typowego laboratorium elektronicznego, bez dodatkowego ekranowania.

EN

The aim of this work is to design a multi-channel mixed-signal system for EEG signal acquisition in brain-computer interfaces. The paper contains a review of EEG signal analysis methods that are used in human-computer communication syste ms. Selected syste ms of this type are described in more detail. A prototype, single-channel sub-system architecture is characterized featuring sufficiently high noise immunity and common-mode rejection to allow EEG signal acquisition. Optical isolation is used for safe circuit operation in a typical office environment. Each channel incorporates 3 integrated-circuit instrumentation amplifiers with a total gain of 80 dB. A single-chip controller is used to work out digital signals to drive 10-bit analog to digital converters. First experimental results are presented, measured using a battery-operated prototype. It is demonstrated that the circuit suppresses very effectively the 50 Hz interference in a typical research laboratory and allows clear detection of alpha-waves via Fourier spectrum analysis of acquired EEG signal, without any special case or shielding. It is expected that the system will be useful to provide a basis for research in the area of development of brain-computer interfaces to technical devices, e.g. as an aid for handicapped persons.