• 제목/요약/키워드: sensory stimulation

검색결과 277건 처리시간 0.027초

Optical imaging of epileptic activity and epilepsy treatments in neocortex

  • Suh, Min-Ah
    • 한국광학회:학술대회논문집
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    • 한국광학회 2009년도 동계학술발표회 논문집
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    • pp.427-428
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    • 2009
  • Optical imaging offers excellent spatio-temporal sensitivity that is unparalleled by any other perfusion based imaging techniques. We used in vivo optical recording of intrinsic signals (ORIS) to map neurovascular hemodynamics of perfusion, oximetry and membrane potential during epileptic events in rat and mouse neocortex. Studies of hemodynamic changes with ORIS alone were also performed in human. Laboratory studies in rodent epilepsy models have demonstrated a persistent increase in deoxygenated hemoglobin (Hbr) and a decrease in tissue oxygenation during interictal spikes and ictal events. This "epileptic dip", like the "initial dip" recorded during normal sensory processing, implies that the enormous rise in cerebral blood flow (CBF) is inadequate to meet the increased metabolic demands associated with synchronized epileptic activity. These findings are critically important to the interpretation of the perfusion-based imaging studies, such as fMRI. In addition, we visualized the effect of direct cortical electrical stimulation, an alterative epilepsy treatment. The optical data following direct cortical electrical stimulation showed that hemodynamic signals are sensitive to different electrical stimulation parameters. Furthermore, our recent data demonstrated that the application of unilateral electrical stimulation is able to elicit bilateral hemodynamic responses in rat neocortex.

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Directing the turning behavior of carp using virtual stimulation

  • Kim, Cheol-Hu;Kim, Dae-Gun;Kim, Daesoo;Lee, Phill-Seung
    • Ocean Systems Engineering
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    • 제7권1호
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    • pp.39-51
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    • 2017
  • Fishes detect various sensory stimuli, which may be used to direct their behavior. Especially, the visual and water flow detection information are critical for locating prey, predators, and school formation. In this study, we examined the specific role of these two different type of stimulation (vision and vibration) during the obstacle avoidance behavior of carp, Cyprinus carpio. When a visual obstacle was presented, the carp efficiently turned and swam away in the opposite direction. In contrast, vibration stimulation of the left or right side with a vibrator did not induce strong turning behavior. The vibrator only regulated the direction of turning when presented in combination with the visual obstacle. Our results provide first evidence on the innate capacity that dynamically coordinates visual and vibration signals in fish and give insights on the novel modulation method of fish behavior without training.

진동자극에 대한 상지 절단자의 전완부 감각 인지 크기와 불쾌감 측정 (The Measurement of the Magnitude of Sensory Perception and Displeasure to the Vibration Stimuli applied on Forearm in upper Limb Amputees)

  • 김솔비;장윤희;김신기;김규석;문무성;배태수
    • 한국정밀공학회지
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    • 제29권7호
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    • pp.705-710
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    • 2012
  • Research involving discomfort or pain related to haptic vibratory stimulation the for prosthesis users of myoelectrical hand is very lacking. Our objective of this study was to evaluate the displeasure and sensitivity of areas in forearm using vibration stimulation system between upper limb amputees and non-amputees. Twenty transradial amputees and forty non-amputees (20 youth, 20 elderly) were involved. We set up custom-made vibration stimulation system including eight actuators (4 medial parts and 4 lateral parts) and GUI-based acquisition system, to investigate changes of residual somatosensory sensibility and displeasure at proximal 25% of forearm. Eight vibration actuators were attached to the circumference of proximal 25% point of forearm at regular intervals. Sensitivity tests were used to stimulate the 120Hz and discomfort experiment was used to 37 ~ 223Hz. The subjective responses were evaluated by 10 point scale. The results showed that both groups were similar in sensitive areas. Response at around of radius was most sensitive than other areas in all subjects. Elderly group do not appear discomfort of vibrotactile; however, youth group and amputee presented discomfort of vibrotactile. Prosthesis with a vibrotactile feedback system should be developed considering the sensitivity. Furthermore, Future studies should investigate the scope of application of that principle.

Effects of Electrical Stimulation on Lipid Oxidation and Warmed-over Flavor of Precooked Roast Beef

  • Cheng, Jen-Hua;Ockerman, Herbert W.
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권2호
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    • pp.282-286
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    • 2013
  • Many manufacturing processes damage the structure of meat products and this often contributes to lipid oxidation which could influence warmed-over flavor (WOF) in precooked beef that is reheated beef. Electrical stimulation causes contraction of muscles and improves tissue tenderization. The purpose of this study was to evaluate the rate of lipid oxidation or warmed-over flavor that could be affected by electrical stimulation of precooked roast beef after refrigerated storage and reheating. The results show that there was no significant difference between chemical compositions and cooking yields when comparing non-electrically stimulated and electrically stimulated roast beef. Moreover, electrical stimulation had no significant effect on oxidative stability and off-flavor problems of precooked roast beef as evaluated by thiobarbituric acid reactive substances (TBARS) and sensory test (warmed-over aroma and warmed-over flavor). However, there was an increased undesirable WOF and a decrease in tenderness for both ES and Non-ES treatments over refrigerated storage time. Electrical stimulation did cause reactions of amino acids or other compounds to decrease the desirable beef flavor in re-cooked meat.

하지에 인가한 전기 자극이 자세안정성에 미치는 영향 (Effects of Postural Stability using Electrical Stimulation on the Lower Limb)

  • 이선연;유미;김동욱;김남균
    • 대한의용생체공학회:의공학회지
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    • 제30권3호
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    • pp.255-262
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    • 2009
  • The present study analyzed the association between postural control and electrical stimulation by measuring body sway when use the electrical stimulations were applied to different stimulation zones in lower limbs. The subjects were 14 young adults and were, tested for two different visual condition: eyes open and eyes closed. The experiments were also performed in two different stance case: one legged stance and two legged stance while electrical stimulations were applied concurrently or individually to tibialis anterior and triceps surae. Postural responses were assessed by analyzing COP sway path, sum of COP sway measured by a forceplate. The results showed that the direction of the COP shift changed in accordance with the direction of stimulation and showed sensory adaptation as the experiment progressed for two legged stance case. For one legged stance case, concurrent electrical stimulation both sides of muscles was found to be effective for enhancement of postural balance control.

감각신경계의 신경생리와 임상적 이용 (Neurophysiology of the Sensory System and Clinical Applications)

  • 서대원
    • Annals of Clinical Neurophysiology
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    • 제12권2호
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    • pp.35-46
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    • 2010
  • Various electrophysiological tests have provided a large body of valuable information on neuronal responses to a presented stimulus. The special and general somatic sensory pathways are main targets of evoked potentials. Two types of evoked potentials, exogenous and endogenous, are commonly used. Exogenous evoked potentials of general and special somatic sensory systems will be reviewed. One of general somatic sensory functional pathways, proprioception, can be evaluated by general somatosensory evoked potentials with electrical stimulation on nerves. The special somatosensory functional pathways, including vision, and audition, can be evaluated by visual evoked potentials and auditory evoked potentials. Also laser-evoked potentials are newly developed for pain pathway, including lateral spinothalamic pathway, and vestibular myogenic evoked potentials for sacculocollic pathways. The evoked potentials of sensory system have maximal clinical utility in evaluating functional deficits along the sensory pathways. They are used for evaluating comatose patients, hysterical patients, premature infants, patients with suspected demyelinating diseases or neoplasms, and research. We discuss the neurophysiologic tests of sensory systems in views of practical points. The organized evaluation of sensory electrophysiologic tests can be helpful in detecting and estimating the abnormalities in neurological diseases.

운전자 스트레스 저감을 위한 다감각 자극의 효과 (Effect of the Multisensory on the Stress-relieving for Vehicle Driver)

  • 김영주;김혜진;이현우;조영호;황민철
    • 감성과학
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    • 제24권4호
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    • pp.107-116
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    • 2021
  • 본 연구의 목적은 운전상황에서 운전자의 스트레스가 유발되었을 시, 다감각 자극이 운전자의 스트레스 저감 효과에 미치는 영향을 분석하였다. 본 연구에서는 운전상황의 운전자의 스트레스를 저감을 목적으로 조명과 사운드 및 향의 조합을 통한 다감각 자극을 제시함으로써, 스트레스 저감에 대한 효과를 확인하고자 하였다. 운전 시 스트레스 상황을 정의하고, 두 종류의 스트레스 유발 시나리오를 구성하였다. 실험은 신체 건강한 20-50대 남녀 30명을 대상으로, 10분간의 운전 상황을 연출하였다. 스트레스 저감에 효과적인 자극조합을 확인하기 위해 시각, 청각, 후각의 자극을 이용하였으며, 시각 자극의 경우 LED 조명을 이용하여 블루, 그린, 옐로우 색상을 제시하였으며, 청각 자극은 화이트, 핑크, 브라운노이즈 사운드를, 후각 자극의 경우는 로즈마리, 라벤더, 레몬향을 각각 사용하였다. 또한, 스트레스 저감에 대한 효과를 살펴보기 위해, 다감각 자극 제시 전후로 주관평가 및 심박변이도를 측정하였다. 심장 반응의 결과, 그린(조명), 핑크노이즈(사운드), 로즈마리(향)의 자극 조합에서 HF(%) 증가 및 LF(%), LF/HF(%)의 감소를 확인할 수 있었으며, 이는 부교감반응의 활성화가 이루어짐을 알 수 있었다. 주관평가 또한 다감각 자극에 노출되었을 때, 다감각 자극이 없는 경우보다 스트레스 저감 효과가 있는 것으로 확인되었다. 이러한 결과는 다감각 자극에 노출되기 전보다 다감각자극을 경험할 때 운전시 스트레스 저감에 효과를 보이는 것으로 사료된다. 향후 연령별이나 성별에 대한 차이나 개인이 선호하는 자극에 대한 연구를 통해 맞춤형 스트레스 저감 자극에 대한 효과를 확인하는 것이 필요하다.

Gender Differences in the Sensitivity and Displeasure Caused by the Vibration Stimuli Applied to the Forearm in Upper Limb Amputees

  • Kim, Sol Bi;Ko, Chang-Yong;Chang, Yun Hee;Kim, Gyoo Suk;Kim, Sin Ki
    • 대한인간공학회지
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    • 제32권4호
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    • pp.355-361
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    • 2013
  • Objective: The aim of this study is to investigate the gender-differences in vibrotactile responses(sensitivity and displeasure) of residual forearm simulated by vibration stimulation in upper limb(trans-radial) amputees. Background: Several studies have reported that vibration stimulation using the haptic vibrator is one the most effective methods for delivering sensation to an amputees. However, few studies have reported the perception to haptic vibratory stimulus, particularly sensitivity and displeasure. Method: We set up a custom-made vibration stimulation system that included 6 actuators(3 medial parts and 3 lateral parts) and a graphical user interface(GUI)-based acquisition system to investigate changes in residual somatosensory sensibility and displeasure in the forearm of upper limb(trans-radial) amputees. Vibration actuators were attached at the 25%-point on the proximal forearm. Stimulation with 32Hz, 64Hz, or 149Hz of frequency was used for the sensitivity tests and with 32~257Hz of frequency was used for the discomfort experiments. The subjective responses were evaluated on a 10 point scale. Results: The results showed that vibrotactile sensory perception in male amputees were higher than that in female amputees. In male amputees, the response at lateral area of forearm was the most sensitive than medial area; but, female amputees showed similar sensitive areas. Subjects did not experience any discomfort during vibrotactile stimuli. Conclusion: Vibrotactile response in the amputees was dependent on gender as well as area stimulated by vibration. Application: The results might contribute to develop the vibrotactile feedback system for the amputees.

배외측전전두엽피질 영역에 경두개직류전류자극이 감각기능에 미치는 영향 (Changes in the Sensory Function after Transcranial Direct Stimulation on Dorsolateral Prefrontal Cortex Area)

  • 민동기
    • 한국산학기술학회논문지
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    • 제16권1호
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    • pp.445-452
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    • 2015
  • 경두개직류전류자극(tDCS)은 낮은 직류 전류 강도를 사용하여 대뇌피질의 자발적인 신경학적 활동의 흥분성을 증가 또는 감소시키는 신경조절 기법이다. 본 연구의 목적은 tDCS를 적용한 후 다양한 감각 기능의 변화를 측정하는데 있다. tDCS의 효과를 측정하기 위해 CPT 검사를 50명의 건강한 대상자에게 단일 기간(8월4일에서 8월29일), 단일 공간, 단일 맹검법으로 무작위 배정하였다. 신경전도검사는 우세 손의 말초신경 병변을 구별하기 위해 정중 감각과 운동신경을 측정하였다. 대상자들은 각 25명 씩 대뇌피질의 DLPFC의 tDCS 자극군과 대뇌피질의 DLPFC의 tDCS 위자극군으로 2개의 다른 조건 아래서 1 mA의 전류강도로 15분씩 양극 tDCS로 적용하였다. 촉각, 빠른 통증과 느린 통증을 각각 평가하기 위해 우세한 제 2수지에 2000, 250, 그리고 5 Hz의 주파수로 CPT 검사인 Neurometer$^{(R)}$를 이용하여 수치들을 기록하였다. DLPFC의 양극 tDCS 자극군의 CPT 수치들에서는 250과 5 Hz에서 통계적으로 유의한 증가를 보였다. 양극 tDCS 위자극군의 모든 CPT 수치들은 감소하였다. 이러한 결과는 DLPFC의 양극 tDCS가 건강한 대상자들의 감각 지각과 통증 역치들을 조절할 수 있다는 것을 보여준다. 따라서 본 연구는 재활과 통증 치료 분야에서 유용한 치료 방법 중 하나로 제시할 수 있을 것으로 생각한다.