• International Journal of Contents
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• 제12권3호
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• pp.12-16
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• 2016

Brain computer interfaces (BCI) usually have focused on classifying the explicitly-expressed intentions of humans. In contrast, implicit intentions should be considered to develop more intelligent systems. However, classifying implicit intention is more difficult than explicit intentions, and the difficulty severely increases for subject independent classification. In this paper, we address the subject independent classification of implicit intention based on electroencephalography (EEG) signals. Among many machine learning models, we use the support vector machine (SVM) with radial basis kernel functions to classify the EEG signals. The Fisher scores are evaluated after extracting the gamma, beta, alpha and theta band powers of the EEG signals from thirty electrodes. Since a more discriminant feature has a larger Fisher score value, the band powers of the EEG signals are presented to SVM based on the Fisher score. By training the SVM with 1-out of-9 validation, the best classification accuracy is approximately 65% with gamma and theta components.

• 제어로봇시스템학회논문지
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• 제19권9호
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• pp.853-859
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• 2013

The purpose of this study was to identify the correlation between electroencephalography (EEG) and strength, using grip strength. 64-channel EEG data were recorded from five healthy subjects in tasks requiring handgrip contractions of nine levels of MVC (Maximal Voluntary Contraction). We found the ERS (Event-Related Synchronization)/ERD (Event-Related Desynchronization) at the measured EEG data using STFT (Short-Time Furier Transform) and spectral power in the EEG of each frequency range displayed in the graph. In this paper, we identified that the stronger we contracted, the greater the spectral power was increased in the ${\beta}$, ${\gamma}$ wave.

• 생물정신의학
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• 제23권3호
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• pp.102-107
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• 2016

This review will summarize EEG studies of learning and memory based on frequency bands including theta waves (4-7 Hz), gamma waves (> 30 Hz) and alpha waves (7-12 Hz). Authors searched and reviewed EEG papers especially focusing on learning and memory from PubMed. Theta waves are associated with acquisition of new information from stimuli. Gamma waves are connected with comparing and binding old information in preexisting memory and new information from stimuli. Alpha waves are linked with attention. Eventually it mediates the learning and memory process. Although EEG studies of learning and memory still have controversial issues, the future EEG studies will facilitate clinical benefits by virtue of more developed and encouraging prospects.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(5)
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• pp.133-136
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• 2002

EEG(Electroencephalography) is generated by electrical activity between neurons in cortical. Waveform of EEG is changed according to body and mental states. Therefore EEG is used to diagnosis of encephalophyma and epilepsy, etc. Also EEG is used to HCI(Human-Computer Interface). This paper describes estimation of orientation and location of dipole sources. The forward model is three-layer spherical head model and current dipole model. Using analytical solution, EEG is generated. Using MNLS(Minimum-Norm Least-Square) method, orientation and location of dipole moment is estimated.

• 수면정신생리
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• 제2권1호
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• pp.31-43
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• 1995

Recently, the methods that measure and analyze brain electrical activity quantitatively have been available with the rapid development of computer technology. The quantitative electroencephalography(QEEG) is a method of computer-assisted analyzing brain electrical activity. The QEEG allows for a more sensitive, precise and reproducible examination of EEG data than that can be accomplished by conventional EEG. It is possible to compare various EEG parameters each other by using QEEG. Neurometrics, a kind of the quantitative EEG. is to compare EEG characteristics of the patient with normative data to determine in what way the patient's EEG deviates from normality and to discriminate among psychiatric disorders. Nowadays, QEEG is far superior to conventional EEG in its detection of abnormality and in its usefulness in psychiatric differential diagnosis. The abnormal findings of QEEG in various psychiatric disorders are also discussed.

• Journal of Yeungnam Medical Science
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• 제29권1호
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• pp.58-60
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• 2012

Central anticholinergic syndrome occurs when an anticholinergic substance works in vivo or as a result of the insufficient release of acetylcholine. Its symptoms include confusion, agitation, behavioral change, hallucination, blurred vision, and dysarthria. Occasionally, these symptoms occur with the use of a scopolamine patch. A 54-year-old female complained of behavioral change and confused mentality. She attached a scopolamine patch at the postauricular area in the morning of the day before her hospital visit. Neurological examination revealed bilateral symmetric mydriasis without light reflex. The brain MRI was normal, and electroencephalography showed nonspecific abnormalities. The patient recovered completely after the removal of the scopolamine patch.

• Annals of Clinical Neurophysiology
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• 제22권1호
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• pp.24-28
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• 2020

Hashimoto's encephalopathy (HE) is a heterogeneous encephalopathy with diverse clinical presentations. Here we report on a 69-year-old woman who presented with confusion, aphasia, fever, and focal ictal discharges. Cerebrospinal fluid analysis and a workup for other fever origins revealed no abnormality and a high level of thyroperoxidase antibody was detected, which findings led to a diagnosis of HE. The symptoms subsided after treatment. This study highlights the importance of considering HE in patients presenting with fever and abnormal EEG findings.

• 대한의용생체공학회:의공학회지
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• 제17권2호
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• pp.209-214
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• 1996

The display of biological signals in raster scan monitors often involves a multirate sampling operation which consists of decimation .and interpolation. All electroencephalouaphic (EEG) samples of 10 to 30 seconds (2, 500 to 7, 500 samples at 250[Hz] sampling frequency) must be displayed in the computer screen to keep the aspect ratio of the paper polygraph output. Since the current afrorclable display technology Plots at most 2, 000 Pixels Per row, sDme signal samples need to be discarde4 This Paper studies methods to perform this operation characterizing them from the signal processing viewpoint and compares the display quality among several decimation techniques. Experimental results show that a nonlinear operation such as the peak detection method could be preferable to the canonical linear filtering to reduce aliasing.

• Annals of Clinical Neurophysiology
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• 제8권1호
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• pp.81-83
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• 2006

Periodic lateralized epileptiform discharges(PLEDs) are usually seen in acute and subacute cerebral lesions. Occasionally PLEDs could be observed in persistent structural lesions. We observed PLEDs-plus in a patient with right basal ganglionic hemorrhage, at 10 months and 13 months after the stroke. The patients suffered two seizures 3 months and 5 days before recording of EEG. PLEDs-plus may persist as an interictal abnormal finding and the rhythmic discharge of that may be increased by a seizure.

• International Journal of Knowledge Content Development & Technology
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• 제3권1호
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• pp.19-29
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• 2013

Insights from the recent wealth of popular books on neuroscience are offered to suggest a strengthening of theory in information science. Information theory has traditionally neglected the human dimension in favour of 'scientific' theory often derived from the Shannon-Weaver model. Neuroscientists argue in excitingly fresh ways from the evidence of case studies, non-intrusive experimentation and the measurements that can be obtained from technologies that include electroencephalography, positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG). The way in which the findings of neuroscience intersect with ideas such as those of Kahneman on fast and slow thinking and Csikszentmihalyi on flow, is tentatively explored as lines of connection with information science. It is argued that the beginnings of a theoretical underpinning for current web-based information searching in relation to established information retrieval methods can be drawn from this.