• Korean Journal of Forensic Psychology
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• v.11 no.1
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• pp.21-36
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• 2020

In P300-based concealed information test (P300 CIT), it evaluates whether the P300 amplitude for the probe is significantly greater than that of the irrelevant to determine if the suspect is telling a lie. An independent sample t-test or a bootstrap method can be used as a statistical test to make that decision. Rosenfeld et al. (2004) used the bootstrap method, claiming that "t tests on single sweeps are too insensitive to use to compare mean probe and irrelevant P300s within individuals" and their method has been accepted to date. The purpose of the study is to evaluate whether the power of t-test is lower than that of the bootstrap method in the P300 CIT. The Monte Carlo study was conducted by using EEG collected from 39 participants. The results showed that the type I error rates of the t-test and the percentile bootstrap method were similar and the power of the percentile bootstrap method was slightly higher than that of the t-test. The type I error rates of the t-test and the percentile bootstrap method were slightly lower than the significance level and the powers of the two tests were also slightly lower than that of the theoretical t-test. On the other hand, the type I error rate and power of the standard error Bootstrap method were the same as those of the theoretical t-test and its power was .012 ~ .081 higher than that of t-test depending on experimental conditions.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.05a
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• pp.49-54
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• 2000

인지 기능의 신경생리적 지표로 널리 사용되고 있는 P300은 정보처리 과정 중 통제정보처리를 반영한다고 알려져 있다. P300 이전에 관찰되는 mismatch negativity 역시 정보처리과정의 초기단계를 반영하며 불수의적 주의력이나 자동적 각성수준 혹은 감각 기억의 기능을 갖고 있다고 한다. 이러한 초기 단계의 과정을 나타내는 mismatch negativity(MMN)가 P300과 어떤 관련을 갖는가를 조사하였다. 실험 결과 Fz와 Cz에서 측정한 MMN의 진폭과 Pz에서의 P300 진폭사이에 유의미한 상관이 있음이 관찰되었다. 이는 정보의 처리가 효율적으로 처리되기 위해서는 처리 과정의 초기 단계인 자동적 정보처리와 통제정보처리가 서로 밀접하게 연관되어 작용한다는 것을 시사한다.

• The Journal of Korean Physical Therapy
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• v.26 no.4
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• pp.234-239
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• 2014

Purpose: The purpose of this study is to use P300 latency to determine whether methods of motor learning in terms of massed and distributed practice can affect motor sequential learning in healthy adults. Methods: Twenty-four healthy subjects participated in this study. They were randomly allocated into three groups: a 10 minute, a 12 hour, and a 24 hour group. In the SRT task, eight numbers were adopted as auditory stimuli. During an experiment, participants were instructed to press the matching key as quickly and accurately as possible when one of the eight numbers was presented randomly. The subjects practiced for three sessions, each of which comprised five blocks of 40 serial reaction time tasks. While they practiced during these three sessions, P300 latency was measured. The data were analyzed using ANCOVA. Results: The P300 latency of Fz, Cz, and Pz decreased in all groups except for the Fz area of the 10 min group. Overall, the P300 latency of the 10 min group showed a smaller decrease compared with the 12 hr and 24 hr groups. Statistically, no significant differences in the Fz and Cz areas were observed among the three groups. The P300 latency in the Pz area of the 10 min group showed a significantly smaller decrease compared with the other groups. Conclusion: These findings suggest that short-term sequential motor training can alter brain functions such as the P300 latency. We also found that better acquisition of a motor skill was obtained with distributed practice of a task than with massed practice.

• Korean Journal of Audiology
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• v.25 no.3
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• pp.119-123
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• 2021

Background and Objectives: The influence of music training on different areas of the brain has been extensively researched, but the underlying neurobehavioral mechanisms remain unknown. In the present study, the effects of training for more than three years in Carnatic music (an Indian form of music) on the discrimination ability of different areas of the brain were tested using P300 analysis at three electrode placement sites. Subjects and Methods: A total of 27 individuals, including 13 singers aged 16-30 years (mean±standard deviation, 23±3.2 years) and 14 non-singers aged 16-30 years (mean age, 24±2.9 years), participated in this study. The singers had 3-5 years of formal training experience in Carnatic music. Cortical activities in areas corresponding to attention, discrimination, and memory were tested using P300 analysis, and the tests were performed using the Intelligent Hearing System. Results: The mean P300 amplitude of the singers at the Fz electrode placement site (5.64±1.81) was significantly higher than that of the non-singers (3.85±1.60; t(25)=3.3, p<0.05). The amplitude at the Cz electrode placement site in singers (5.90±2.18) was significantly higher than that in non-singers (3.46±1.40; t(25)=3.3, p<0.05). The amplitude at the Pz electrode placement site in singers (4.94±1.89) was significantly higher than that in non-singers (3.57±1.50; t(25)=3.3, p<0.05). Among singers, the mean P300 amplitude was significantly higher in the Cz site than the other placement sites, and among non-singers, the mean P300 amplitude was significantly higher in the Fz site than the other placement sites, i.e., music training facilitated enhancement of the P300 amplitude at the Cz site. Conclusions: The findings of this study suggest that more than three years of training in Carnatic singing can enhance neural coding to discriminate subtle differences, leading to enhanced discrimination abilities of the brain, mainly in the generation site corresponding to Cz electrode placement.

• Journal of Audiology & Otology
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• v.25 no.3
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• pp.119-123
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• 2021

Background and Objectives: The influence of music training on different areas of the brain has been extensively researched, but the underlying neurobehavioral mechanisms remain unknown. In the present study, the effects of training for more than three years in Carnatic music (an Indian form of music) on the discrimination ability of different areas of the brain were tested using P300 analysis at three electrode placement sites. Subjects and Methods: A total of 27 individuals, including 13 singers aged 16-30 years (mean±standard deviation, 23±3.2 years) and 14 non-singers aged 16-30 years (mean age, 24±2.9 years), participated in this study. The singers had 3-5 years of formal training experience in Carnatic music. Cortical activities in areas corresponding to attention, discrimination, and memory were tested using P300 analysis, and the tests were performed using the Intelligent Hearing System. Results: The mean P300 amplitude of the singers at the Fz electrode placement site (5.64±1.81) was significantly higher than that of the non-singers (3.85±1.60; t(25)=3.3, p<0.05). The amplitude at the Cz electrode placement site in singers (5.90±2.18) was significantly higher than that in non-singers (3.46±1.40; t(25)=3.3, p<0.05). The amplitude at the Pz electrode placement site in singers (4.94±1.89) was significantly higher than that in non-singers (3.57±1.50; t(25)=3.3, p<0.05). Among singers, the mean P300 amplitude was significantly higher in the Cz site than the other placement sites, and among non-singers, the mean P300 amplitude was significantly higher in the Fz site than the other placement sites, i.e., music training facilitated enhancement of the P300 amplitude at the Cz site. Conclusions: The findings of this study suggest that more than three years of training in Carnatic singing can enhance neural coding to discriminate subtle differences, leading to enhanced discrimination abilities of the brain, mainly in the generation site corresponding to Cz electrode placement.

• Korean Journal of Biological Psychiatry
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• v.10 no.2
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• pp.168-176
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• 2003

Objectives:We investigated the characteristics of P300 generators in obsessive-compulsive disorder(OCD) patients by using voxel-based statistical parametric mapping of current density images. Methods:P300 generators, produced by a rare target tone of 1500Hz under a frequent non-target tone of 1,000Hz, were measured in 15 right-handed OCD patients and 15 controls. Low Resolution Electromagnetic Tomography(LORETA), using a realistic head model of the boundary element method based on individual MRI, was applied to the 128-channel EEG. Statistical parametric mapping(SPM) was applied for the statistical analysis. Results:We found that both groups had the mean current density of P300 in the parietal, temporal and prefrontal lobe. There was a trend for decreased current density in the prefrontal area in OCD patients. The statistical comparison showed current density increase in the supraparietal area, a statistically significant longer P300 latency and a trend for reduced P300 amplitude in OCD patients. Conclusion:It suggests that P300 source of both groups exists in multiple brain regions at the same time. And both groups had no statistically significant differences in the current density of P300 except for increased current density in the supraparietal area in OCD patients. But, considering the statistically significant longer P300 latency, a trend for reduced P300 amplitude and relative mean current density reduction in the prefrontal area in OCD patients, this study suggests that the frontal lobe may have a reduced normal inhibitory process in OCD patients.

• Science of Emotion and Sensibility
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• v.18 no.2
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• pp.85-100
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• 2015

This study aimed at examining if the original memory remains after a misinformation is presented, using Event-Related Potential based Concealed Information Test (ERP-based CIT). In the first stage of the study, the participant was presented with either the original information or a misleading information after experiencing an event (Post-information). The second stage was to measure brain wave and reaction time on the original, misleading, and irrelevant information (CIT-Stimulus). P300 amplitude, P300 area, P300 latency, and reaction time were used as dependant variables. In the result, a significant Post-information ${\times}$ CIT-Stimulus interaction effect was found on the P300 area measured at Cz, Pz, and Oz area. This interaction effect implied the possibility that the original information could be partially impaired in memory by misleading information presented afterward. P300 amplitude at Pz area did not differ between the accurate and the misleading stimuli in the condition in which a misleading information was presented. This result can be explained by source monitoring error. In discussion, the limitations of this study and directions of future studies were discussed.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.193-195
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• 2003

The analysis of EEG data is an important task in the domain of Brain Computer Interface (BCI). In general, this task is extremely difficult because EEG data is very noisy and contains many artifacts and consists of mixtures of several brain waves. The P300 component of the evoked potential is a relatively evident signal which has a large positive wave that occurs around 300 msec after a task-relevant stimulus. Thus automatic detection of P300 is useful in BCI. To this end, in this paper we employ a method of reference-based independent component analysis (ICA) which overcomes the ordering ambiguity in the conventional ICA. We show here. that ICA incorporating with prior knowledge is useful in the task of automatic P300 detection.

• Science of Emotion and Sensibility
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• v.18 no.1
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• pp.39-48
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• 2015

It is known that P300-based concealed information test (P300 CIT) was not greatly affected by the traditional countermeasures. This study was to test whether P300 CIT is affected by the new countermeasures. We used three types of countermeasures. First type was a sequential countermeasure in which participants had to respond in alternating ways to irrelevants by pressing the left index finger covertly when the encountered irrelevant firstly, by wiggling the right big toe inside the shoe when encountered irrelevant secondly, by imaging his or her mother's name when encountered irrelevant thirdly, and by imaging his or her father's name when encountered irrelevant fourthly until all stimuli were presented. Second type was a partial matching and physical countermeasure. Participants in this type were asked to press the left index finger imperceptibly after one of the irrelevants and wiggle the right big toe after another of the irrelevants. Third type was a partial matching and mental countermeasure. Participants were required to imagine mother's name for one irrelevant and father's name for another irrelevant. The results showed that contrary to our expectation, the use of sequential countermeasure increased the detection rate from 77% to 92%. The partial matching countermeasure had a negative effect on P300 CIT. The physical countermeasure decreased the detection rate from 77% to 46%, and the mental countermeasure decreased the detection rate from 100% to 69%. The necessity for the development of methods to prevent or detect countermeasure is discussed.

• Korean Journal of Cognitive Science
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• v.16 no.2
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• pp.141-154
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• 2005

The purpose of this study was to investigate the effects of implicit and explicit situation awareness instruction on decision making and event related brain potentials. Psychophysiological data obtained from 36 intermediated level tennis players whose National Tennis Rating Program(NTTP) belong 2 to 2.5 were compared. Participants were randomly assigned to one of three experimental groups: (1) implicit situation awareness, (2) explicit situation awareness, and (3) control group. A total of 90 clips were presented via a beam project screen, and participants pressed one of three jelly bean buttons to indicate the direction of ball hit. Dependent measures were the latencies and amplitudes of P300 on Pz, Cz, and Fz. The results of this study indicated that participants in the implicit situation awareness produced tenser P300, than participants in the explicit situation awareness group. The findings also indicated that single defense showed longer P300 latencies than single attack as well as double defense. The P300-amplitude of treatment groups were longer than control group. The Cz area showed shorer P300 latencies than Pz and Fz areas. In addition, single defense situation demonstrated longer P300 latencies than single attack and double defence situations. Based on this study, it is believed that implicit and explicit situation awareness instruction influence decision making in different ways.