• Journal of the Optical Society of Korea
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• 제16권2호
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• pp.145-150
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• 2012

We present a display-based visual stimulator for psychophysical and electrophysiological visual sensitivity measurements. The stimulator offers various psychophysical visual stimuli and transfers the signals from external devices along with the stimulation signals to an electrophysiological recorder. As an experimental demonstration, we perform a visual sensitivity experiment in the mesopic vision range by using the display-based stimulator. The intensity of the steady-state visual evoked potential is observed to correlate with the luminance of the flickering visual stimulation. For the psychophysically determined detection thresholds, we determine the mesopic luminance, showing agreement with the perceived brightness within the uncertainty of the luminance measurement.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권1호
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• pp.79-86
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• 2013

We describe a neural stimulator front-end with arbitrary stimulation waveform generator and adaptive supply regulator (ASR) for visual prosthesis. Each pixel circuit generates arbitrary current waveform with 5 bit programmable amplitude. The ASR provides the internal supply voltage regulated to the minimum required voltage for stimulation. The prototype is implemented in $0.35{\mu}m$ CMOS with HV option and occupies $2.94mm^2$ including I/Os.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.359-359
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• 2002

Brain Stimulator processes both visual and audible stimulus and send them human sensory organ. The stimulus was accepted by our sensory organ effect upon human mental function. In this study, we examine the actual effect of commercial brain stimulator using tMRI system.

• Investigative Magnetic Resonance Imaging
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• 제1권1호
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• pp.114-118
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• 1997

목적: 기능적 MR 영상은 외부자극에 따라, 이에 상응하는 특정한 뇌피질 부위의 혈류량의 변화를 신호강도의 차이로 나타내는 방법이다. 시각피질에 대한 기능적 MR은 환자가 광자극을 응시함으로써 수행될 수 있는 것으로, 이의 수행에는 적절한 형태의 광자극원이 필수적이다. 이에 저자는 광자극원의 크기가 시각피질 활성화에 영향을 미칠 수 있는지 알아보기 위하여 본 연구를 하였다. 대상 및 방법: 정상적인 시력을 가진 자원자 5명을 대상으로 시각활성화 기능적 MR을 시행하였다. 광자극원은 $11{\times}8cm$ 크기의 기판에 적색 LED(light-emitting diodes) 39개를 박고 직류전원을 사용하도록 만들었다. 이를 크기에 따라 full field, half field 및 focal central field의 3가지로 구분하고 8Hz로 점멸하였다. EPI 기법으로 6회의 광자극 기간과 6회의 휴식기간을 번갈아 3차례 시행하여 총 36회의 검사를 하고, Z-score로 통계처리하였다. 이 때 얻은 활성화 영상을 같은 부위의 T1강조영상에 결합시켰다. 각 경우에서 시각피질에서 활성화된 pixel의 수를 full field, half field 및 focal central field에서 얻어진 pixel 수의 합으로 나누어 활성화지수를 구하였다. 이 활성화지수를 토대로 광원크기와의 관계를 분석하였다. 결과: Full field로 자극을 주었을 때 시각피질의 평균 신호강도의 증가는 약 9.6%였다. 4명에서 활성화지수는 full field, half field, focal central field의 순으로 감소하였으며, 나머지 1명에서는 half field 시의 값이 full field 시의 값보다 컸다. 광원크기에 따른 활성화지수의 범위는 full field 43-73%(평균 55%), half field 22-40%(평균 32%), focal central field 5-24%(평균 13%)였다. 결론: 기능적 MR영상을 이용하여 시각피질의 활성화를 용이하게 확인할 수 있었으며 광자극원의 크기에 따라 증가되는 시각피질 활성화를 입증할 수 있었다.

• The Korean Journal of Pain
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• 제18권2호
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• pp.156-160
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• 2005

Background: Frozen shoulder is not an uncommon disease, which is associated with chronic pain and joint movement limitation. However, there are numerous devices to assist in the treatment of shoulder pain, but their efficacy has not been proven and their use remains immensely controversial. Therefore, a randomized clinical study was conducted to determine the effectiveness of a low-frequency stimulator for the treatment of frozen shoulder. Methods: A randomized clinical trial was carried out on 40 patients with frozen shoulder, with 40 patients assigned to two groups; a control treatment group (group C, n = 20) and a low frequency stimulator application group (group T, n = 20). Both groups were given a routine treatment modality, such as trigger point injection, intramuscular stimulation or suprascapular nerve block etc. The level of the shoulder pain was evaluated using a 100mm VAS (visual analog scale) at each visit, with the limitation in the range of motion simultaneously evaluated. Results: All the subjects improved after treatment, with the VAS scores after termination of treatment showed a statistically significant reduction (P < 0.05). However, there was no significant difference between the two groups. One month after termination of 5 cycles of treatment, group T maintained their improved state, whereas the pain in some of those in group C reemerged, which also showed a statistically significant difference (P < 0.05). The limitation in the range of motion improved, with most subjects able to resume daily activity. Conclusions: Although the low frequency stimulation provided no more pain relief than routine treatment, the effect was significantly prolonged. From this result, low frequency stimulation can be considered to aide the therapeutic effect of classical frozen shoulder therapy.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권5호
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• pp.658-665
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• 2014

The neural stimulators have been employed to the visual prostheses system based on the functional electrical stimulation (FES). Due to the size limitation of the implantable device, the smaller area of the unit current driver pixel is highly desired for higher resolution current stimulation system. This paper presents a 16-channel compact current-mode neural stimulator IC with digital to analog converter (DAC) sharing scheme for artificial retinal prostheses. The individual pixel circuits in the stimulator IC share a single 6 bit DAC using the sample-and-hold scheme. The DAC sharing scheme enables the simultaneous stimulation on multiple active pixels with a single DAC while maintaining small size and low power. The layout size of the stimulator circuit with the DAC sharing scheme is reduced to be 51.98 %, compared to the conventional scheme. The stimulator IC is designed using standard $0.18{\mu}m$ 1P6M process. The chip size except the I/O cells is $437{\mu}m{\times}501{\mu}m$.

• 한국조경학회지
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• 제26권1호
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• pp.36-43
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• 1998

We compared the electroencephalogram, blood pressure, and sensory evaluation inspectioni several color of Petunia hybrida to analyze the physiopsychological effects of a plant. Considering occipital is related to visuosensory field, green color is thought as mild visual stimulator unlike to pink color. The results are coincident with the well-known facts that green color is less stimulating color. It is also accorded with the sensory evaluation results that green color showed te feeling of blue and stable. In case of green color is showed the feeling of blue and stable. In case of green color the generatioin of alpha waves increased according to the increase color area. Therefore it is thought that green color helps decrease of visual stimulation and increase in visual stability. However it is thought that pink has less physiopsychological effects on human beings depending on area sizes than green has.

• Journal of Acupuncture Research
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• 제34권1호
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• pp.89-96
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• 2017

Objectives : The aim of the study was to ascertain the effectiveness of magnetic acupuncture in patients with plantar fasciitis. Methods : The patients were treated with magnetic acupuncture using a magnetic therapy stimulator (Whata 153), as well as with moxibustion therapy. Acupuncture treatment was conducted on the acupoints of Ashi-as well as on 太谿 (KI3), 崑崙 (BL60), and 委中 (BL40)-for 15 minutes. The intensity of pain was evaluated using the visual analogue scale (VAS), and the tenderness threshold (TT) was measured at each visit using an algometer. Results : After treatment, evaluation using the VAS had improved, as had the TT; furthermore, plantar fasciitis pain was reduced. Conclusion : Magnetic acupuncture relieved pain in plantar fasciitis. In further clinical study, more research on magnetic acupuncture is required.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 춘계학술대회
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• pp.260-265
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• 1996

The purpose of this study was to implemented a general purpose programmable nerve stimulator system as a research tool for studying psychophysiological performance associated with various stimulation waveform. This system is composed of hardware and software, the former are the personal computer(180586) and control unit(one-chip microprocessor, D/A converter, digital output), the latter are programmed in VISUAL BASIC and ASSEMBLY Which are programmed for the programmable nerve stimuli pattern editor and communication interface, waveform preprocessing, and stimuli generator. The control unit which is entrolled by the personal computer is capable of delivering the programmable nerve stimuli waveform. This system has research potential for determining the effect of various neuromuscular blockade in alternated physiological stat is.

• 대한물리치료과학회지
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• 제9권1호
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• pp.1-8
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• 2002

This study set out to investigate what kind of effects the consistent visual stimuli and verbal and non verbal auditory stimuli have on pain alleviation, as well as to see the influence of joint application of visual and auditory stimuli at the same time on pain alleviation, according to lightness of 50lux and 200lux, ultimately providing basic data in setting up an environment in case of treating pain. The subject were comprised of 30 male and female adults with pain in the neck and back area. The subject were treated in their pain area with Transcutaneous Electrical Nerve Stimulator(TENS) 100HZ for 20 minutes in the research set where each visual, auditory, and joint visual and auditory stimuli was given. For analysis methods, Visual Analogue Scale(VAS) and McGill Pain Questionnaire were adopted to see the changes before and after treatment, and the electrocardiogram, systolic and diastolic pressure, number of heart rate and breathing frequence and endorphin were compared and analyzed using the Wilcoxon singed-rank test. And The Kreskal-walllis test was used to compare the two subgroups from each group. Wilcoxon singed-rank test and the Kreskal-walllis test was used to compare the two subgroups from each group. The results were as follows: 1. The group of 50lux and 200lux were compared given varying degrees of visual stimuli. The group of 200lux showed more reduction in pain points, average systolic and diastolic pressure and average endorphin. 2. The group of verbal and non verbal were compared given varying degrees of auditory stimuli. The group of non-verbal showed more reduction in average systolic and diastolic pressure. 3. The group of 200lux+verbal and 200lux+non verbal were compared given varying degrees of joint visual and auditory stimuli. There was found a statistical significance(p<0.05) in endorphin between the two groups, with more endorphin reduction for 200lux+non verbal group. And there was a statistically significant reduction in VAS and McGill before and after the treatment between the two groups.