• Journal of Biomedical Engineering Research
• /
• v.29 no.1
• /
• pp.17-24
• /
• 2008

The aim of this paper is to report our preliminary results of investigating the spatial focalization of Zen-meditation EEG (electroencephalograph) in alpha band (8-13 Hz). For comparison, the study involved two groups of subjects, practitioners (experimental group) and non-practitioners (control group). To extract EEG alpha rhythm, wavelet analysis was applied to multi-channel EEG signals. Normalized alpha-power vectors were then constructed from spatial distribution of alpha powers, that were classified by Fuzzy C-means based algorithm to explore various brain spatial characteristics during meditation (or, at rest). Optimal number of clusters was determined by correlation coefficients of the membership-value vectors of each cluster center. Our results show that, in the experimental group, the incidence of frontal alpha activity varied in accordance with the meditation stage. The results demonstrated three different spatiotemporal modules consisting with three distinctive meditation stages normally recognized by meditation practitioners. The frontal alpha activity in two groups decreased in different ways. Particularly, monotonic decline was observed in the control group, and the experimental group showed increasing results. The phenomenon might imply various mechanisms employed by meditation and relaxation in modulating parietal alpha.

• Korean Journal of Acupuncture
• /
• v.30 no.4
• /
• pp.305-318
• /
• 2013

Objectives : The aim of this study was to examine the effect of electroacupuncture(EA) at an acupoint, HT8(Sobu), on normal humans by using power spectral analysis. We examined the effect on the Heart Rate Variability(HRV), and the balance of the autonomic nervous system. Methods : Thirty-two healthy volunteers participated in this study. EEG(Electroencephalogram) power spectrum exhibits site-specific and state-related differences in specific frequency bands. A thirty-two channel EEG study was carried out on thirty-two subjects(14 males; mean age=23.5 years old, 18 females; mean age=21.5 years old). HRV and EEG were simultaneously recorded before and after acupuncture. Results : In the ${\alpha}$(alpha) band, during the HT8-acupoint treatment, the power values in the ${\alpha}$(alpha) band significantly decreased(p<0.05) at 28 channels. In the ${\beta}$(beta) band significantly decreased(p<0.05) at 26 channels. In ${\delta}$(delta) band significantly decreased(p<0.05) at 18 channels. In ${\theta}$(theta) band significantly decreased(p<0.05) at 20 channels. ${\alpha}/{\beta}$ values were increased at 6 channels and decreased at 10 channels.${\beta}/{\theta}$ values were increased at 10 channels and decreased at 19 channels. Mean-RR(RR-interval), Complexity, RMSSD(Root mean square of successive differences), SDSD(Standard deviations differences between adjacent normal R-R intervals), norm HF showed a significantly increased and mean-HRV, norm LF, LHR(LF/HF Ratio) showed a significantly decreased after HT8-acupoint treatment(p<0.05). Conclusions : These results suggest that EA at the HT8 mostly causes significant changes on alpha(28 channels), beta(26 channels), delta(18 channels), theta(20 channels) bands and mean-HRV, mean-RR, complexity, RMSSD, SDSD, norm LF, norm HF and LHR. If practicing EA at the HT8, it will regulate the function of the cerebral cortex, decrease activity of the sympathetic and increase parasympathetic nervous activity.

• Journal of Institute of Control, Robotics and Systems
• /
• v.19 no.6
• /
• pp.527-533
• /
• 2013

BCI (Brain-Computer Interface) is a system that transforms a subject's brain signal related to their intention into a control signal by classifying EEG (electroencephalograph) signals obtained during the imagination of movement of a subject's limbs. The BCI system allows us to control machines such as robot arms or wheelchairs only by imaging limbs. With the exact same experiment environment, activated brain regions of each subjects are totally different. In that case, a simple approach is to use as many channels as possible when measuring brain signals. However the problem is that using many channels also causes other problems. When applying a CSP (Common Spatial Pattern), which is an EEG extraction method, many channels cause an overfitting problem, and in addition there is difficulty using this technique for medical analysis. To overcome these problems, we suggest an optimal channel selection method using a BPSO (Binary Particle Swarm Optimization), BPSO with channel impact factor, and GA. This paper examined optimal selected channels among all channels using three optimization methods and compared the classification accuracy and the number of selected channels between BPSO, BPSO with channel impact factor, and GA by SVM (Support Vector Machine). The result showed that BPSO with channel impact factor selected 2 fewer channels and even improved accuracy by 10.17~11.34% compared with BPSO and GA.

• Korean Institute of Interior Design Journal
• /
• v.22 no.5
• /
• pp.171-178
• /
• 2013

In this study, we sought to find out the effect of different emotional interior images of the community facilities in an apartment complex on a youth brain wave by analyzing an Electroencephalograph (EEG). Based on the frequency of usage, we selected learning facilities, cultural facilities, and sport facilities. For brain stimulation, the visual stimulants with three different emotional words, cheerful, gentle, and elegant, were used based on I.R.I image scale. Overall, total nine different emotional images were used. Based on our findings, we conclude that: first, in order to improve learning concentration of the youth, a learning facility for the youth needs to be designed by skillfully combining the soft and comfortable colors from the gentle image and the murky and dark colors from the elegant image. Second, when designing a cultural facility, it is preferable to consider the elegant image for a calm and comfortable space. Third, a sport facility design needs to preclude dark colors and apply light colors to create a dynamic and lively space. Furthermore, we found out that the youth has established static images of each functionally different facility through their experience and learning. Therefore, it is imperative to plan community facilities in an apartment complex in a way to connect the space function with the emotional characteristics of the youth in order to support and encourage energetic activities and learning of the community youth.

• Journal of KIISE:Software and Applications
• /
• v.27 no.1
• /
• pp.24-32
• /
• 2000

BCI(Brain-Computer Interface) is studied to control the machines with brain. In this study, an EEG(Electroencephalography) signal classification model is proposed. The model gets EEG pattern from each subject's brain and extracts characteristic features. The model discriminates the EEG patterns by using those extracted characteristic features of each subject. The proposed method classifies each pair of the given tasks and combines the results to give the final result. Four tasks such as rest, movement, mental-arithmetic calculation and point-fixing were used in the experiment. Over 90% of the trials, the model yielded successful results. The model exploits characteristic features of the subjects and the weight table that was produced after training. The analysis results of the model such as its high success rates and short processing time show that it can be used in a real-time brain-computer interface system.

• Journal of Digital Convergence
• /
• v.16 no.12
• /
• pp.343-349
• /
• 2018

Electroencephalograph(EEG) information, which is an important data of brain science, reflects various levels of information from the molecular level to the behavior and cognitive stages, and the explosively amplified information is provided at each stage. Therefore, EEG information is an intrinsic privacy area of an individual, which is important information to be protected. In this paper, we apply spring security to web based system of spring MVC (Model, View, Control) framework to build independent and lightweight server system with powerful security system. Through the proposal of the platform type EEG analysis system which enhances the security function, the web service security of the EEG information is enhanced and the privacy of the EEG information can be protected.

• Journal of Korea Entertainment Industry Association
• /
• v.14 no.6
• /
• pp.289-299
• /
• 2020

The purpose of this study was to confirm the effect of mindfulness education on perceived stress, mindfulness, psychological well-being, and brain waves. The study used a repeated-measures design to examine 42 female university students currently enrolled in mindfulness courses. Subjects participated in the mindfulness course once a week for eight weeks, 50 minutes per session. The main outcome variables, such as perceived stress, mindfulness, and psychological well-being, were measured with a structured questionnaire and brain waves were measured with an electroencephalograph. The same variables were then measured after the completion of the eight-week course. The results demonstrate that perceived stress significantly decreased from 1.85±0.39 to 1.66±0.39 points (t=3.44, p=.001), while, on the other hand, mindfulness increased from 3.10±0.26 points to 3.19±0.32 points (t =-2.78, p=.008). There was also a significant difference in the level of autonomy, a subcategory of psychological well-being (t=-2.70, p=.010). In addition, EEG indicated significant changes in the frequencies of Theta channel 19 and Rapid Alpha channels 7 and 10. These results suggest that further studies are needed to elucidate the effects of mindfulness education through the modification of mindfulness course plans, diversification of teaching methods, and improvement in the educational environment.

• The Korean Society of Law and Medicine
• /
• v.24 no.3
• /
• pp.125-153
• /
• 2023

The Supreme Court's en banc decision on December 12, 2022 (docket number 2016Do21314) presented a new standard for determining whether the use of diagnostic medical devices by Korean medical doctors constitutes oriental medical doctors constitutes unlicensed medical practice. Based on this standard, it was determined that the use of ultrasound by Korean medical doctors was not an unlicensed medical practice. Supreme Court's Decision 2016Du51405 on August 18, 2023, is the first case in which a new standard was applied to determine that an Korean medical doctor's use of electroencephalography to diagnose Parkinson's disease and dementia was not an unlicensed medical practice. The Supreme Court abolished the previous standard that Western medical knowledge and technology should not be required for Korean medical doctors to use medical devices. However, it was unclear whether Western medical diagnosis of Korean medical doctors using diagnostic medical devices would be viewed as an an auxiliary method of diagnosis. Parkinson's disease and dementia are Western medical diagnoses. The Supreme Court judged that the Western medical diagnosis of Korean medical doctors was not an unlicensed medical practice. This clearly explains what an auxiliary method of diagnosis means. In addition, the Supreme Court excluded the principles of development and production of electroencephalography from its judgment criteria. Automatic extraction and automatic reading of test results were also excluded. The criminal court's view that the meaning of oriental medical practice should be clearly and strictly interpreted from the perspective of an oriental doctor, and it was clarified that diagnostic medical devices were excluded from criminal punishment unless it was clear that they were not related to the principle of oriental medical practice. As a result, the Supreme Court made it clear that the use of diagnostic medical devices is excluded from criminal punishment unless it is clear that they are not related to the principles of Korean medicine.