• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.3
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• pp.59-67
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• 2008

Due to the fast increase in cellular phone users, public interest on health effect of electromagnetic fields(EMFs) by cellular phonos is gradually increasing. Some EHS(electromagnetic hypersensitivity) patients complain of psycho-neurophysiological symptoms such as headaches, insomnia, memory loss resulting from RF radiation by CDMA cellular phones. However, EHS is difficult to diagnose and depends on the individual's subjective judgement. And we don't know clearly if the cause of EHS is uneasiness or real exposure. There have been various EHS volunteer studies on heart rate, blood pressure and subjective symptoms using GSM phones. But there are few studies on experimental case-control study investigating physiological parameters, subjective symptoms, and perception of EMFs. In this study, two volunteer groups of 17 self-declared EHS and 19 controls were exposed to both sham and real RF exposure by CDMA cellular phones for half an hour each. We investigated not only the physiological parameters such as heart rates, respiration rates and HRVs(hear rate variability), but also the perception of EMFs and subjective symptoms. As the results, EMF exposure did not have any effects on the subjective symptoms or physiological parameters for both groups. For the EMF perception, there was no evidence that EHS group perceived the EMFs correctly than the control group.

• Journal of Preventive Medicine and Public Health
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• v.25 no.1 s.37
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• pp.26-33
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• 1992

The carpal tunnel syndrome is one of the most common peripheral nerve entrapment syndromes. The typical symptoms are pain, numbness and paresthesia in the median nerve territory of the hand. Recently, it is widely recognized that occupational factor is regarded as the important cause of the carpal tunnel syndrome. Clinical study is performed in the 42 female workers who is repetitively working at packing department in a rayon manufacturing factory from November 1991 till March 1992. The study included a questionnaire, physical examinations, and the neurophysiological test. The summary of the results obtained was as follows : 1. Among 42 packing workers, 9 workers(21.4%) were diagnosed as carpal tunnel syndrome by electromyography. The affected side was bilateral in 4 workers(9.5%), right in 4 workers(9.5%), and left in one worker(2.4%). 2. Among 42 subjects, 28 workers(66.7%) complained the clinical symptoms related to carpal tunnel syndrome, 11 workers(26.2%) showed positive Phalen sign, and 7 workers(16.7%) showed positive Tinel sign. 3. Researchers regard electromyographic finding as the gold standard for diagnosis of carpal tunnel syndrome. The sensitivity and specificity of the clinical symptoms to diagnose the carpal tunnel syndrome were 0.89, 0.39 respectively. If the carpal tunnel syndrome is diagnosed by the combination of the positive findings of the symptoms and the physical examinations, either Tinel or Phalen sign, the sensitivity and specificity were 0.67 and 0.76 respectively. Considering above results, though this small number of workers is not adequate for epidemiologic conclusions, carpal tunnel syndrome seems to be an important occupational disorder among packing workers in a rayon manufacturing factory.

• Korean Journal of Psychosomatic Medicine
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• v.8 no.1
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• pp.122-140
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• 2000

Somatization disorder is a chronic condition characterized by multiple somatic complaints that are not due to any apparent organic illness. Somatization disorder is related historically to hysteria and hysteria has been defined by the existence of somatic complaints for which no organic reason can be found. Therefore most theories of somatization have focused on the psychodynamic and sociological perspectives. However, the concept that the somatic presentation of emotional distress or psychiatric illness might have a neurobiological basis has also aroused considerable interest. Relative to this perspective, the case of Anna O. which has been considered the prototype of hysteria, was reformulated from a neuropsychological perspective. Several neurophysiological and neuropsychological studies, studies concerning hemispheric differences in symptom presentation of the patients with hysteria have been shown the evidences for the biological basis of somatization. Moreover, recent neuroimaging studies in somatization disorder also show that brain dysfunction in somatization. The author reviewed several candidate theories which could help to explain the process of somatization in the perspective of biological basis and proposed the new neuropsychological model of somatization. The author also examined the possible application of this model to the treatment of somatization disorder and discussed it's limitation and the future directions in this field.

• The Journal of Korean Physical Therapy
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• v.17 no.3
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• pp.339-350
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• 2005

This study is the quasi-experimental study on the gait training rehabilitation. The purpose of this study is to prepare the baseline data for most suitable of gait while we were scrutinizing how the walking characters, functional walking ability, gait quality of stroke patients were affected by the gait on BWSTT (Body Weight Supported Treadmill Training) through the change of treadmill velocity and body weight support. To accomplish this purpose, this study used thirty subjects, more than 3 months post stroke, for rehabilitation who were divided between two gait training groups they received the neurophysiological physical therapy. For 6 weeks, 5 times a week for 15 minutes per session, the BWSTT group participated in 30 sessions structured speed-dependent treadmill training with 30% body weight supported, and the ratio of body weight support was gradually decreased as the patients advanced the capability of more self-support. The OGT(Over Ground Training) group received the same quantity of equal sessions like BWSTT. Firstly, we measured the absolute improvement of walking velocity (m/s), capacity(min/m) and cadence(steps/min) among walking characters. Secondly, we measured the functional walking ability such as Functional Ambulatory Category(FAC, score out of 5), Modified Motor Assesment Scale(MMAS, score out of 6) and Gait Quality Chart(score out of 41). Data analysis was performed with using SPSS 10.0 win program. The descriptive analysis was used to obtain average and standard deviation. The independent t-test and the paired t-test were used to compare both the groups about pre and post training test. Treatment effects were established by pre and post assessment. Subjects tolerated the training well without side-effects. Therefore, the results of this study were as follows; 1. There was a more significant difference from the improvement of walking velocity(0.09m/s), endurance(4.53min/m), cadence(4.20steps/min), FAC(0.26score), MMAS(0.33 score) and hip joint and pelvic of gait quality(0.39 score) ever before in the BWSTT group(p<.05). 2. There was a more significant increase from the walking velocity(0.01m/s) in the OGT group(p<.05). 3. There was a more statistical significant increase from comparing the average of walking velocity in both groups ever before(0.42m/s in BWSTT group and 0.31m/s in OGT group)(p<.05). There was a statistical significant difference from the average of cadence in both groups(61.87step/min in BWSTT group and 3.60steps/min in OGT group)(p<.05). As we can see from above, the findings suggest that BWSTT may be more effective than the OGT for improving some gait parameters such as gait velocity and cadency. This conclusion also suggest that BWSTT is more effective for the improvement of gait of stroke patients.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.1-11
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• 1998

Ameliorating mechanisms of red ginseng on learning deficits were investigated in the following 3 experiments; its effects on 1) place learning deficits in aged rats and in young rats with selective hippocampal lesions (behavioral study), 2) long-term potentiation in the hippocampal formation (neuro- physiological study), and 3) ChAT (choline acetyl transferase) activity in various brain regions of aged rats (pharmacological study). In the behavioral study, first, performance in the place learning tasks were compared among 3 groups of young and aged rats; control young intact rats (10-12 week old) treated with water, aged rats (28-32 month old) treated with water, and aged rats (28-32 month old) treated with red ginseng (100 mghglday) suspended in water. Second, performance in the place learning tasks was compared among 3 groups of young rats; control intact rats treated with water, rats with bilateral hippocampal lesions treated with water, and rats with bilateral hippocampal lesions treated with red ginseng (100 mg/kg/day). Each rat in these 2 behavioral experiments was tested with the 3 types of the place learning tasks in a circular open field using intracranial self-stimulation (ICSS) as reward. The ICSS reward was delivered if the rat (1) moved distance of 100-160 cm (DMT): (2) entered an experiment-determined reward place within the open field, and this place was randomly varied in sequential trials (RRPST); or (3) entered 2 specific places, and did a shuttle behavior between the 2 places (PLT). Performance of the aged rats in the ginseng group was not significantly different from that of control young rats in ICSS (current intensity, bar press rates), DMT and RRPST. However, treatment with red ginseng significantly ameliorated place-navigation learning deficits in aged rats in the PLT. Similarly, red ginseng ameliorated learning and memory deficits in young rats with hippocampal lesions in the same tasks. In the neurophysiological study using young rats, perfusion of hippocampal slices with non-sapon in fraction of red ginseng significantly enhanced magnitudes of the long-term potentiation (LfP) in the CA3 subfield. In the pharmacological study, treatment with red ginseng did not affect ChAT activity in aged rat brain including the hippocampal formation. These results strongly suggest that red ginseng ameliorates learning and memory deficits in aged rats through actions on the CA3 subfield of the hippocampal formation, which were independent of the presynaptic components of the cholinergic system

• Physical Therapy Rehabilitation Science
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• v.4 no.1
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• pp.28-31
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• 2015

Objective: Psychomotor imagery has been widely used to improve motor performance and motor learning. Recent research suggests that during visualization, changes occur in neurophysiological networks that make physical practice more effective in configuring functional networks for skillful behaviors. The aim of our pilot study was to determine if there was change and to what extent there was differentiation in modulation in electroencephalography (EEG) frequencies between visualizing a state of rest and a state of exercise performance and to identify the preponderant frequency. Design: Quasi-experimental design uncontrolled before and after study. Methods: EEG brain wave activity was recorded from 0-40 Hz from nine cerebral cortical scalp regions F3, Fz, F4, C3, Cz, C4, P3, POz, and P4 with a wireless telemetric EEG system. The subjects, while sitting on a chair with eyes closed, were asked to visualize themselves in a state of routine rest/relaxation and after a period of time in a state of their routine exercise performance. Results: The gamma frequency, 31-40 Hz, (${\gamma}$) was the predominant wave band in differentiation between visualizing a state of rest versus visualizing a state of exercise performance. Conclusions: We suggest these preliminarily findings show the EEG electrocortical activity for athletes is differentially modulated during visualization of exercise performance in comparison to rest with a predominant ${\gamma}$ wave band frequency observed during the state of exercise. Further controlled experimental studies will be performed to elaborate these observations and delineate the significance to optimization of psychomotor exercise performance.

• Tuberculosis and Respiratory Diseases
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• v.76 no.2
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• pp.75-79
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• 2014

Trichloroethylene (TCE) is a toxic chemical commonly used as a degreasing agent, and it is usually found in a colorless or blue liquid form. TCE has a sweet, chloroform-like odor, and this volatile chlorinated organic chemical can cause toxic hepatitis, neurophysiological disorders, skin disorders, and hypersensitivity syndromes. However, the hypersensitivity pneumonitis (HP) attributed to TCE has rarely been reported. We hereby describe a case of HP associated with TCE in a 29-year-old man who was employed as a lead welder at a computer repair center. He was installing the capacitors on computer chip boards and had been wiped down with TCE. He was admitted to our hospital with complaints of dry coughs, night sweats, and weight losses for the past two months. HP due to TCE exposure was being suspected due to his occupational history, and the results of a video-associated thoracoscopic biopsy confirmed the suspicions. Symptoms have resolved after the steroid pulse therapy and his occupational change. TCE should be taken into consideration as a potential trigger of HP. Early recognition and avoidance of the TCE exposure in the future is important for the treatment of TCE induced HP.

• The Journal of Korean society of community based occupational therapy
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• v.8 no.3
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• pp.69-76
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• 2018

Objective : The study was to investigate the neurophysiological approach to the effect of complex exercise on memory, one of brain functions, and the degree of sleep disorder using experimental animals with sleep disorders. Methods : This study carried out a complex exercise that designed in an animal laboratory for 4 days to 16 sleep - disordered model rats. After the exercise, brain function was confirmed with the changes of BDNF in the hippocampus and the change of sleep level was confirmed with the concentration of melatonin in the blood. Results : First, the effect of the complex exercise program on brain function was significantly increased in the experimental group(p<0.01). Second, the effect of complex exercise program on sleep disturbance was significantly increased in the experimental group and control group(p<0.01)(p<0.05). Conclusion : The rate of increase of the elderly in the community is rapidly increasing, and the sleep disorder of the elderly can affect the quality of life of these elderly people. Secondary memory impairment due to sleep disturbances can also be a problem. Although there are many ways to improve sleep disturbance, it has been scientifically proven through experimental animals that sleep and memory can be improved with complex exercise that is not economically, spatially burdensome.

• Journal of Electrodiagnosis and Neuromuscular Diseases
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• v.20 no.2
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• pp.98-105
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• 2018

Objective: To evaluate whether the increase of the amplitude of motor evoked potentials (MEPs) during surgery can imply favorable prognosis postoperatively in spinal cord tumor surgery. Method: MEPs were monitored in patients who underwent spinal cord tumor surgery between March 2016 and March 2018. Amplitude changes at the end of monitoring compared to the baselines in limb muscle were analyzed. Minimum and maximum changes were set to $MEP_{min}$ (%) and $MEP_{max}$ (%). Strengths of bilateral 10 key muscles which were documented a day before ($Motor_{pre}$), 48 h ($Motor_{48h}$) and 4 weeks ($Motor_{4wk}$) after the surgery were reviewed. Results: Difference of $Motor_{48h}$ from $Motor_{pre}$ ($Motor_{48h-pre}$) and $Motor_{4wk}$ from $Motor_{pre}$ ($Motor_{4wk-pre}$) positively correlated with $MEP_{min}$, suggesting that smaller the difference of MEPs amplitude, less recovery of muscle strength. There was a negative correlation between the amount of bleeding and $MEP_{min}$, indicating that the greater the amount of bleeding, the smaller the $MEP_{min}$, implying that MEPs amplitude is less likely to improve when the amount of bleeding is large. It also showed significant difference between patients with improved or no change of motor status and patients with motor deterioration after surgery according to anatomical tumor types. Conclusion: Improve of muscle strength was less when the increase of MEPs amplitude was small, and improvement of MEPs amplitude was less when the amount of bleeding was large. Correlation between changes of status of muscle strength after surgery and tumor types was observed. With amplitude increase in MEPs monitoring, restoration of muscle strength can be expected.

• Journal of Korean Neurosurgical Society
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• v.64 no.1
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• pp.78-87
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• 2021

Objective : Intraoperative neurophysiological monitoring (IONM) has been widely used during spine surgery to reduce or prevent neurologic deficits, however, its application to the surgical management for cervical myelopathy remains controversial. This study aimed to assess the success rate of IONM in patients with cervical myelopathy and to investigate the factors associated with successful baseline monitoring and the effect of increasing the stimulation intensity by focusing on motor evoked potentials (MEPs). Methods : The data of 88 patients who underwent surgery for cervical myelopathy with IONM between January 2016 and June 2018 were retrospectively reviewed. The success rate of baseline MEP monitoring at the initial stimulation of 400 V was investigated. In unmonitorable cases, the stimulation intensity was increased to 999 V, and the success rate final MEP monitoring was reinvestigated. In addition, factors related to the success rate of baseline MEP monitoring were investigated using independent t-test, Wilcoxon rank-sum test, chi-squared test, and Fisher's exact probability test for statistical analysis. The factors included age, sex, body mass index, diabetes mellitus, smoking history, symptom duration, Torg-Pavlov ratio, space available for the cord (SAC), cord compression ratio (CCR), intramedullary increased signal intensity (SI) on magnetic resonance imaging, SI length, SI ratio, the Medical Research Council (MRC) grade, the preoperative modified Nurick grade and Japanese Orthopedic Association (JOA) score. Results : The overall success rate for reliable MEP response was 52.3% after increasing the stimulation intensity. No complications were observed to be associated with increased intensity. The factors related to the success rate of final MEP monitoring were found to be SAC (p<0.001), CCR (p<0.001), MRC grade (p<0.001), preoperative modified Nurick grade (p<0.001), and JOA score (p<0.001). The cut-off score for successful MEP monitoring was 5.67 mm for SAC, 47.33% for the CCR, 3 points for MRC grade, 2 points for the modified Nurick grade, and 12 points for the JOA score. Conclusion : Increasing the stimulation intensity could significantly improve the success rate of baseline MEP monitoring for unmonitorable cases at the initial stimulation in cervical myelopathy. In particular, the SAC, CCR, MRC grade, preoperative Nurick grade and JOA score may be considered as the more important related factors associated with the success rate of MEP monitoring. Therefore, the degree of preoperative neurological functional deficits and the presence of spinal cord compression on imaging could be used as new detailed criteria for the application of IONM in patients with cervical myelopathy.