• Journal of Biomedical Engineering Research
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• v.20 no.3
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• pp.307-314
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• 1999

This paper describes an informatlon compression of electrically evoked myoelectric signal, M-wave. This wave shows a direct response m lato-response of nerve conductlQn study and has a characteristic with finite time support. M-wave is a useful factor for investing neurodi~ease and is often desirable to have a compact description of its shape and time evolution. The aim of this paper is to show that the AR modeling IS a effective method for compressing an information of M-wave. First, AR model parameters of real M-wave are estimated. And then. they are verified by approximatmg a M-wave using estimated AR parameters and by comparing to other melhod, Hermite tlansform[4]. To concretely evaluate the proposed method, the NMSE(normalized mean square error) of approximation curves are compared. As a result, AR modeling is effective for M-wave assessment because of its capability for the information compression.

• Annals of Clinical Neurophysiology
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• v.8 no.2
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• pp.163-170
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• 2006

Backgrounds: MEG can measure the task-specific neurophysiologic activity with good spatial and time resolution. Language lateralization using noninvasive method has been a subject of interest in resective brain surgery. We purposed to develop a paradigm for language lateralization using MEG and validate its feasibility. Methods: Magnetic fields were obtained in 12 neurosurgical candidates and one volunteer for language tasks, with a 306 channel whole head MEG. Language tasks were word listening, reading and picture naming. We tested two word listening paradigms: semantic decision of meaning of abstract nouns, and recognition of repeated words. The subjects were instructed to silently name or read, and respond with pushing button or not. We decided language dominance according to the number of acceptable equivalent current dipoles (ECD) modeled by sequential single dipole, and the mean magnetic field strength by root mean square value, in each hemisphere. We collected clinical data including Wada test. Results: Magnetic fields evoked by word listening were generally distributed in bilateral temporoparietal areas with variable hemispheric dominance. Language tasks using visual stimuli frequently evoked magnetic field in posterior midline area, which made laterality decision difficult. Response during task resulted in more artifacts and different results depending on responding hand. Laterality decision with mean magnetic field strength was more concordant with Wada than the method with ECD number of each hemisphere. Conclusions: Word listening task without hand response is the most feasible paradigm for language lateralization using MEG. Mean magnetic field strength in each hemisphere is a proper index for hemispheric dominance.

• Korean Journal of Acupuncture
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• v.17 no.1
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• pp.67-73
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• 2000

The purpose of the present study is to determine the effect of Radix Stemonae on histamine induced tracheal smooth muscle contraction in guinea pigs. Guinea pig(500g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine (His) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine ($10^{-7}∼10^{-4}M$). Contractions evoked by His ($ED_{50}$) were inhibited significantly by Radix Stemonae. In guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 87.4% (p<0.01) after $100{\mu}l/ml$ Radix Stemonae. Following treatment with propranolol, the mean percent inhibition caused by $100{\mu}l/ml$ Radix Stemonae fell to 16.2% in guinea pig induced by histamine contraction. Indomethacin and methylene blue($10^{-7}M$) did not significantly alter the inhibitory effect of Radix Stemonae. These results indicate that Radix Stemonae can relax histamine induced contraction of guinea pig tracheal smooth muscle, and that this inhibition involves sympathetic effects.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.83-93
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• 1997

Rhizoma Coptidis, a traditional herb medicine, has been used in Korea and China for many centuries as a treatment for many disease. The purpose of the present study was to determine the effect of Rhizoma Coptidis on histamine-induced tracheal smooth muscle contraction in guinea pigs and rats. Guinea pigs(500g, male) and rats(250g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from each guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine ($10^{-7}-10^{-3}M$). Contractions evoked by histamine($ED_{50}$) were inhibited significantly by Rhizoma Coptidis. The mean percent inhibition was 33.2% after 1.5mg/ml Rhizoma Coptidis, and 69.5% after 5.0mg/ml Rhizoma Coptidis in guinea pigs, and the mean percent inhibition was 25.3% after 1.5mg/ml Rhizoma Coptidis, and 65.8% after 5.0mg/ml Rhizoma Coptidis in rats. Indomethacin ($10^{-7}M$) slightly but significantly attenuated the inhibitory effects of Rhizoma Coptidis. But propranolol and methylene blue ($10^{-7}M$) did not significantly alter the inhibitory effect of Rhizoma Coptidis. These results indicate that Rhizoma Coptidis can relax histamine-induced contraction of guinea pig and rat tracheal smooth muscle, and that this inhibition involves, in part, cyclooxygenese inhibitor.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.14 no.2
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• pp.83-87
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• 2003

Background and Objectives : Sphincteric function of the larynx, essential to lower airway protection, is most efficiently achieved through strong reflex adduction by both vocal cords. We hypothesize that central facilitation is an essential component of a bilateral adductor reflex and that its disturbance could result in weakened sphincteric closure. Materials and Method : Seven adult 20kg dogs underwent evoked response laryngeal electromyoraphy under 0.5 to 1.0 MAC isoflurane anesthesia. The internal branch of superior laryngeal nerve was stimulated through bipolar platinum-iridium electrodes and recording electrodes were positioned in the ipsilateral and contralateral thyroaryteonoid muscles. Results : Consistent threshold responses were obtained ipsilaterally under all anesthetic levels. However, contralateral reflex responses disappeared as anesthetic levels approached 1.0 MAC. Additionally, at 0.5 MAC, late responses (R2) were detected in one animal. Conclusion : Alteration of central facilitation by deepening anesthesia abolishes the crossed adductor reflex, predisposing to a weakened glottic closure response. Precise understanding of this effect may improve the prevention of aspiration in patients emerging from prolonged sedation or under heavy psychotropic control.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.291-296
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• 1998

In the experiment carried out on 20 college students, recorded were frontal, temporal and occipital EEG, skin conductance response, skin conductance level, heart rate and respiration rate during listening to two music fragments with different affective valences and white noise administered immediately after negative visual stimulation. Analysis of physiological patterns observed during the experiment suggests that affective auditory stimulation with music is able to selectively modulate autonomic and cortical activity evoked by preceding aversive visual stimulation and to restore initial baseline levels. On other hand, physiological responses to white noise, which does not possess emotion-eliciting capabilities, evokes response typical for orienting reaction after the onset of a stimulus and is rapidly followed by habituation. Observed responses to white noise were similar to those specific to attention only and had no evidence for any emotion-related processes. Interpretation of the obtained data is considered in terms of the role of emotional and orienting significance of stimuli, dependence of effects on the background physiological activation level and time courses of attention and emotion processes. Physiological parameters are summarized with regard to their potential utility in differentiation of psychological processes induced by auditory stimuli.

• Journal of Biomedical Engineering Research
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• v.32 no.1
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• pp.74-78
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• 2011

Although recent studies have shown the usibility of [F-18]FDG small animal Positron Emission Tommography (PET) as a functional neuroimaging technique in behavioural small animal study, researches showing the detection power of functional changes in the brain are still limited. Thus, in the study, we performed [F-18]FDG small animal PET neuroimaging in the well-established fear behavioural experiment. Twelve rats were exposed on cat for 30 minutes after the [F-18]FDG injection. As a result, the brain activity in bilateral amygdala areas significantly increased in the fear condition. In addition, the fear condition evoked the functional activities of hypothalamus, which seemed to be related to the response to stress. These clear localization of fear related brain regions may reflect that a functional neuroimaging technique using [F-18]FDG small animal PET has functional detectibility enough to be applied in small animal behavioral research.

• Korean Journal of Veterinary Research
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• v.15 no.2
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• pp.199-201
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• 1975

In order to investigate the effect of aconitine upon the parasympathetic innervation, the isolated rabbit duodenal preparation pretreated with atropine and tetrodotoxin were observed. The results obtained in this work were summerized as follows: 1. The excitatory response was evoked by the administration of aconitine ($100{\mu}g/ml$). 2. The contraction was blocked by the pretreatment with atropine ($10{\mu}g/ml$). 3. The contraction was completely blocked by the pretreatment with tetrodotoxin($10{\mu}g/ml$). These experimental evidences indicate that the excitatory response by aconitine is due to the parasympathetic nerves.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.52
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• pp.203-210
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• 1999

We report on some of the preliminary results of the physiological responses resulting from vehicular speed changes. Healthy human subjects (n=5) were studied for the experiments. We measured the physiological responses of the subjects such as Heart Rate Variability (HRV), Galvanic Skin Response (GSR), and skin temperature for day and night vehicular speed change experiments, respectively. Before and after the tasks, we carried out a self-report for acquiring correlation with experiment results. Mean heart rate variability (HRV) and amplitude of GSR and skin temperature were calculated for 3 minutes duration in each state. The analysis of the physiological measures of ANS activity revealed that vehicle speed change-based affective state evoked arousal response pattern featured by HR acceleration, decrease of skin temperature, and increase of GSR amplitude. The obtained results show that despite some differences observed between each state, overall physiological responses show that the activity of the sympathetic nervous system increases as a result of the increase of speed.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.985-994
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• 2000

Objective : There are some advantages of trigeminal evoked potential(TEP) recording compared to other somatosensory evoked potential(SSEP) recordings. The trigeminal sensory pathway has a pure sensory nerve branch, a broader receptive field in cerebral cortex, and a shorter pathway. Despite these advantages, there is little agreement as to what constitutes a normal response and what wave forms truly characterize the intraoperative TEP. This study presents the normative data of TEP recorded on the epidural surface of the rat with a platinum ball electrode. Materials & Methods : Under general anesthesia with urethane, the adult Sprague-Dawley male rats(300-350g) were given electrical stimulation with two stainless steel electrodes which were inserted into the subcutaneous layer of the area around whiskers. A reference electrode was positioned in the temporalis muscle ipsilateral to the recording site. Results : TEPs were recorded in the Par I area of somatosensory cortex and recorded most apparently on the point of 2mm posterior from the bregma and 6mm lateral from the midline. The typical wave form consisted of 5 peaks (N1-P1-N2-P2-N3 according to emerging order, upward negativity). Each latency to corresponding peaks was not influenced by the different intensities of stimulation, especially from 1 to 5mA. Average latencies of 5 peaks were in the following order ; 7.7, 11.1, 15, 22.3, 29.4ms. There was also no significant difference between latencies before and after administration of muscle relaxant(pancuronium). For the electrophysiological localization of recorded waves, the action potential of a single unit was recorded with glass microelectrode(filled with 2M NaCl, $3-5M{\Omega}$) in the thalamus of rat. A sharp wave was recorded in the VPM nucleus, in which the latency was shorter than that of N1. This suggests that all 5 peaks were generated by neural activities in the suprathalamic pathway. Conclusion : In terms of recording near-field potentials, our data also suggests that TEP in the rat may be superior to other SSEPs. In overall, these results may afford normative data for the studies of supratentorial lesions such as hydrocephalus or cerebral ischemia which can have an influence on near-field potentials.