• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1310-1312
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• 1996

In this study, the algorithm for detection of evoked potentials is proposed. The observed evoked potentials are first preprocessed by blind identification so as to eliminate the ongoing EEG Bile noise. Then, statistic characteristics of the peak components i.e latency and amplitude are detected from prefiltered responses by latency-corrected averaging method. The performance of blind identification is compared with those of adaptive fillers as to deterministic and stochastic EPs, is assessed in terms of NMSE, distortion index, correlation coefficient with original EPs. The estimated deterministic and stochastic EPs restored with peak components are compared and assessed. The results show the superiority of this proposed algorithm using blind identification in detecting deterministic and stochastic EPs.

• Annals of Clinical Neurophysiology
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• v.20 no.1
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• pp.18-25
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• 2018

Evoked potentials (EPs) measures the electrophysiologic responses of the nervous system to variety of stimuli. In clinical practice, only a few are used on a routine basis. Because of the small amplitude of EPs recorded by noninvasive methods, computer summation or averaging generally is necessary to resolve them from background noise. Therefore, waveform acquisition under good condition according to standard method is important. We aimed to provide the standards for clinical EP equipment, technical consideration and minimal requirements for obtaining good clinical EP waveforms, and general criteria for writing EP reports in practice as Korean guidelines.

• Journal of Korean Physical Therapy Science
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• v.3 no.1
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• pp.907-918
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• 1996

Evoked potentials(EP) are defined as electric responses of the nerves system to sensory stimulation. EPs are used mainly to test conduction in the visual, auditory, and somatosensory systems, especially in the central parts of these systems. Somatosensory evoked potentials (SEP) are the potentials elicited by stimulation of peripheral nerves and recorded at various sites along the sensory pathway. SEPs types consist mainly of SEPs to electric stimulation of arm or leg nerves. SEPs to arm stimulation are usually recorded simultaneously from clavicular, cervical, and scalp electrodes; SEPs to leg stimulation are recorded from lumbar, low thoracic, and scalp electrodes. Subject variables that have practical impotance are age, limb length, body height, and temperature. General clinical interpretation of abnormal SEPs wave decreases of peripheral conduction time, and abolition of SEPs recorded from different levels to identify lesions of peripheral nerves, plexus, nerve root, spinal cord, cauda equina, hemispheric brainstem, and cerebral parts of the somatosensory pathway.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.171-174
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• 1992

Development of a noninvasive intensive care system calls for the use of evoked potentials (EPs), as a means of diagnosing traumatic head-injured patients. The experiment entails surgically plating two subarachnoid bolts and a subdural balloon through the skull to simulate a subdural hematoma. Using various levels of intracranial pressure (ICP) and/or different sizes of balloons, auditory evoked potentials (AEPs) were recorded from a rabbit. Six positive peat latencies ($P_1-P_6$) and five negative peak latencies ($N_1-N_5$) were extracted from an averaged AEP waveform. Multiple regression analyses were performed for determining a relationship between the ICP and AEP peak latencies. The results indicate that a major correlation of changes on AEP peak latencies is due to mechanical forcer of a mass (inflated balloon simulating a hematoma) in the distortion of the brain matter rather than increased ICP.

• Journal of Biomedical Engineering Research
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• v.16 no.2
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• pp.167-174
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• 1995

Development of a noninvasive intensive care system calls for the use of evoked potentials (EPs) as a means of diagnosing traumatic head-injured patients. The experiment entails surgically placing two subarachnoid bolts and a subdural balloon through the skull to simulate a subdural hematoma. Using various levels of intracranial pressure (ICP) and/or different sizes of balloons, auditory evoked potentials (AEPs) were recorded from a rabbit. Six positive peak latencies ($P_1 - P_6$) and five negative peak latencies ($N_l- N_5$) were extracted from an averaged AEP waveform. Multiple regression analyses were performed for determining. a relationship between the ICP and AEP peak latencies. The results indicate that a major correlation of ch, mges on AEP peak latencies is due to mechanical forces of a mass (inflated balloon simulating a hematoma) in the distortion of the brain matter rather than increased ICP itself.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.10
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• pp.89-97
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• 1997

To extract time-varying evoked potential (EP), segement latency corrected average method is presented. This method is composed of three steps. First, adaptive filtering for reducing the effect of artifacts and removing background noise is performed. Next, validated intervals of individual segments are aligned, and latency components are detected by cross-correlation between the previously obtained and measured EPs within the intervals. Finally, after the detected latency component, responses of segments are groupe and averaged, the shole corrected EP signal is obtained. In the experiments, the resutls of the conventional methods including simple averaging, Woody's method, and peak component latency corrected averaging are obtained, the results compared with the present method for evaluating performance. Therefore, the presented method confirms that it reflects the latency variations of fundamental peaks and gets the improved EP.