• Journal of The Korean Society of Integrative Medicine
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• v.8 no.2
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• pp.131-138
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• 2020

Purpose : The purpose of this study was to investigate the effects of the frequency band pass filter on the P300 event-related potential in the working memory. Methods : The subjects were 20 women in their 20s who applied for participation in the experiment. Event-related potentials (ERPs) were elicited using 3-back tasks for the working memory, and were recorded from Fz, Cz, and Pz scalp electrodes. The high-pass filters were set to 0.01, 0.1, and 0.3 Hz for analysis purposes, and the low-pass filters were set to 30 and 15 Hz. The 3-back task was presented for a total of 100 times, among which 30 times were designated for the target stimulation (a matched number) and 70 times for the non-target stimulation (an unmatched number). The temporal interval between each stimulation was set at 1 second, while each time duration was randomly presented between 2 to 4 seconds. ERP were analyzed for the P300 recorded from Fz, Pz and Cz scalp electrodes. Results : Latency and amplitude had no significant interaction effects in both the high- and low-pass filters. For the main effects, the latency and amplitude of the P300 event-related potential had no significant difference in the high-pass filters, but the latency had a significant difference in the low-pass filter of Fz, and the amplitude had a significant difference in the low-pass filter of Pz. Conclusion : The results of this study showed that the less than 0.3 Hz high filters had no effects on the differences between the latency and amplitude of the P300 event-related potential in the working memory. The 30Hz low-pass filter, however, was found to be useful for recording the P300 event-related potential in the working memory.

• Journal of information and communication convergence engineering
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• v.8 no.2
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• pp.234-237
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• 2010

P300 component of the event-related potential(ERP) has been studied for theoretical, empirical, and clinical applications. Nowadays the 1-, 2-, and 3-stimulus oddball paradigms are used for eliciting P300 component of EEG in the auditory stimulus experiments. In this paper, we used a method to add one more stimulus to the 3-stimulus auditory paradigm. The adding stimulus has not the same volume but the same tone of the target stimulus. The 4-stimulus oddball paradigm to use two targets is used to elicit the P300 event-related potentials. In 4-stimulus oddball paradigm, an infrequent non-target (p=0.10) is presented in addition to two infrequent targets (p=0.10) and a frequent standard (p=0.70). Two target stimuli elicited a P300 component with a parietal maximum distribution. The amplitude of the P300 in target 2 was larger than that in target 1 and the latency of the P300 in target 2 was longer than that in target 1. The P300 component due to target 2 stimuli was larger than that due to target 1 stimuli. The experimental results approve that the 4-stimulus oddball paradigm can elicit P300 component clearly. The results are compared with the results of the traditional oddball paradigm.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.180-185
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• 2000

Objective : The present study was designed to compare Global Field Power Measurement and conventional method in P300 determination. Method : The subjects were composed of patients(N=20) with schizophrenia by DSM-IV and normal controls(N=20). The auditory event related potential P300 was measured by "oddball paradigm". P300 components were determined by Global Field Power Measurement and conventional method at 5 electrodes(Fz, Cz, Pz, $T_3$, $T_4$). Results : P300 amplitudes of patients were smaller than those of controls across all electrodes and in both methods, but there was no differential power in P300 determination between two methods. Asymmetry of auditory event-related potential P300 was not shown between patients with schizophrenia and normal controls. Conclusion : It is implicated that it depends on clinical situations and research purposes what method of P300 determination will be more appropriate for patients with schizophernia.

• Journal of information and communication convergence engineering
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• v.9 no.2
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• pp.125-128
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• 2011

P300 component of the event-related brain potential (ERP) reflects fundamental cognitive processes. The P300 components have been employed in a wide variety of theoretical, empirical, and clinical applications. In oddball paradigm for eliciting P300, we need standard stimuli and target stimuli. Firstly, designated stimuli are presented to subjects. Nextly, a chosen target stimulus is presented. In this paper, we elicited the P300 components with experiment that the subjects select a chosen target stimulus. Therefore, we measured the P300 components to be related choice of the target stimuli. The experimental results and the P300 components to be analyzed were presented.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.11a
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• pp.148-152
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• 2002

This study is to develop the Alzheimers disease (AD) detection and analysis system using event-related potential (ERP) of AD patients. We recorded ERP in an auditory oddball paradigm in mild AD (n=25), severe AD (n=12), age-matched normal aged controls (n=17), and young controls (n=7). The amplitude and latency of target P300 components were compared among 4 groups. The relationship between P300 measures and neuro psychological test (K-DRS) scores were evaluated by correlations. The latency of P300 was prolonged in AD and the effects were correlated with the severity of dementia. The P300 amplitude was not affected significantly in AD. Theres no difference between normal aged group and young group. These results suggest that the P300 component is specifically affected by Alzheimer type dementia.

• Sleep Medicine and Psychophysiology
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• v.1 no.1
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• pp.76-86
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• 1994

Objectives: This research was performed in order to observe the neuropsychological implication and functional anatomical source of event related potentials(ERP) by studying of correlations between event related potentials and neuropsychological tests. Methods: The latency and voltage of P100 of visual evoked potential (VEP), and N120 and P300 of event related potentials were studied in 56 patients and their correlations with neuropsychological tests were computed. Results: The tests showing significant correlation with latency P100 were visual continous performance test(VCPT) and contingent continous performance test(CCPT) without any significant correlation with voltage of P100. In latency of N120 category test and verbal IQ of KWIS showed significant correlation, and in voltage of N120, finger tapping test, VCPT, CCPT and digit symbol test displayed significant correlations. The latency of P300 had significant correlation with trail making A test and Stroop test. In the voltage of P300 significant correlations were shown with trail making B test, digit symbol test and Wechsler memory scale, finger tapping test, stroop test, VCPT and CCPT. Conclusion : N120 may be considered to reflect the function of medial frontal lobe and P300 may be considered to be developed from the subcortical connection of medial temporal lobe, hippocampus, thalamus, basal ganglia and medial frontal lobe.

• Korean Journal of Biological Psychiatry
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• v.11 no.1
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• pp.40-48
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• 2004

Objective:Event-related potentials(ERPs) are electrical changes recorded at the surface of the scalp in response to stimulus presentation, and their latency and amplitude change according to cognitive processes. Through past studies of the auditory ERP in schizophrenia, the P300 has been reported to be statistically smaller and delayed in schizophrenia than comparison groups. However, studies of the visual ERP have not been systematically examined. The present study was designed to investigate the visual P300 in patients with schizophrenia and normal controls and to compare the pattern of P300 between them. Methods:The subjects were composed of patients(N=22) with schizophrenia by DSM-IV and normal controls(N=22). The visual ERPs were measured by the visual continuous performance test. P300 amplitude and latency measured on 5 scalp electrodes(Fz, Cz, Pz, $T_7$, $T_8$) were compared between patients and controls. Results:The P300 latencies measured on Fz, Cz, Pz, and $T_7$ electrodes were significantly longer in patients than controls(p<0.05). The P300 amplitudes in patients were smaller than controls. However, the difference between them was not statistically significant. Conclusion:Analysis of the visual ERPs showed that the P300 latency is significantly delayed and the P300 amplitude is slightly smaller in patients than controls. These results are similar to established studies of the auditory P300 in schizophrenia.

• Journal of Biomedical Engineering Research
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• v.30 no.4
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• pp.306-310
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• 2009

The purpose of this study is to observe the change in gamma-band cortical activities (GBAs) due to task difficulty. Event-related potential and gamma-band activity were investigated using electroencephalograms recorded during auditory oddball tasks with two difficulty levels. For more difficult task, the amplitude of P300 decreased and the peak latency of P300 was delayed significantly compared to easier task. The induced GBA decreased considerably during the P300 latency period and the peak latency of the induced GBA was delayed for more difficult task. The results imply that the difficulty-related change in cortical information processing may be implemented as a change in the strength of local neuronal association.

• Journal of Biomedical Engineering Research
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• v.29 no.1
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• pp.73-81
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• 2008

The purpose of this study is to observe the brain activity patterns during visual oddball tasks with two difficulty levels by the analysis of high-density event-related potential (ERP). Along with conventional statistical analysis of averaged ERP waveforms, we applied independent component analysis (ICA) for the individual, single-trial analysis and verified its effectiveness. We could identify multiple ERP components such as early visual components (P1, N1), and two components which seem to be important task-related components and showed difficulty-dependent variability (P2, P300). The P2 was found around central region at $180{\sim}220ms$, and the P300 was found globally at $300{\sim}500ms$ poststimulus. As the task became difficult, the P2 amplitude increased, and the P300 amplitude decreased. After single-trial ERPs were decomposed into multiple independent components (ICs), several ICs resulting from P2 and P300 sources were identified. These ICs were projected onto scalp electrodes and the projected ICs were statistically compared according to two task difficulties. For most subjects, the results obtained from single-trial/individual analysis using ICA gave the tendencies of amplitude change that are similar to the averaged ERP analysis for most subjects. The temporal pattern and number of ICs corresponding to ${\mu}$ rhythm was not dependent on the task difficulty. It seems that the motor response was not affected by the task difficulty.

• Journal of the Korean Society of Safety
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• v.15 no.1
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• pp.167-175
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• 2000

Work performance and human error are complicated phenomena so that it is very difficult to grasp the true nature of them. However, Event Related Potential (ERP) may give a clue to them because human brain reflects diverse psychophysiological process. In the present study, the possibility of ERP application to the ergonomic area was evaluated in view of grasping error symptoms. For that purpose, the subjects were asked to count specific characters in a random character matrix on a computer monitor, and their ERP was compared with their performance data. Based upon the results, the amplitude of P300 was not so high as that in the case of the Odd Ball tasks, correct response corresponded with stable ERP with high P300 amplitude whereas wrong response did with unstable, fluctuating ERP with low P300 amplitude. Those results coincided with the work performance, and it was concluded that 3-wave fluorescent with illumination level of 800 lux would be recommendable for the counting task in concern. Conclusively, ERP including P300 might supply an objective clue to the problem of human errors in cognitive process.