• 대한통합의학회지
• /
• 제7권1호
• /
• pp.9-17
• /
• 2019

Purpose : This study assessed the effects of transcranial direct current stimulation (tDCS) on balance, fall efficacy, and fall-related fitness in stroke patients, using a cohort of 30 stroke patients divided into two groups. Methods : The experimental group (was given transcranial direct current stimulation in a virtual reality program) and the control group was given false tDCS in virtual reality. there were 15 patients in each group, receiving appropriate treatment over 30 sessions (30 minutes per session per week over a six-week period). In order to assess the change in balance before and after the intervention, the Berg Balance scale was utilized. Fall efficacy was evaluated using the Korean Falls Efficacy Scale for the Elderly (FES-K), The following exercises were performed by patients to assess fall-related fitness : sitting down in a chair and standing up : walking a 244 cm round= trip, and standing on one foot. Results : After the intervention, the experimental group exhibited significantly increased fall efficacy and fall-related fitness, while the control group exhibited no change. These findings suggest that tDCS has positive effects on balance, fall efficacy, and fall-related fitness in stroke patients. Conclusion : Using tDCS as an intervention would bring positive effects on balance, fall efficacy, and fall-related fitness in stroke patients undergoing rehabilitation.

• 대한의용생체공학회:의공학회지
• /
• 제44권6호
• /
• pp.377-383
• /
• 2023

Purpose: There is increasing attention to the application of transcranial direct current stimulation (tDCS) for enhancing cognitive functions in subjects to aging, mild cognitive impairment (MCI), and Alzheimer's disease (AD). Despite varying treatment outcomes in tDCS which depend on the amount of current reaching the brain, there is no general information on the impacts of anatomical features associated with AD on tDCS-induced electric field. Objective: The objective of this study is to examine how AD-related anatomical variation affects the tDCS-induced electric field using computational modeling. Methods: We collected 180 magnetic resonance images (MRI) of AD patients and healthy controls from a publicly available database (Alzheimer's Disease Neuroimaging Initiative; ADNI), and MRIs were divided into female-AD, male-AD, female-normal, and male-normal groups. For each group, segmented brain volumes (cerebrospinal fluid, gray matter, ventricle, rostral middle frontal (RMF), and hippocampus/amygdala complex) using MRI were measured, and tDCS-induced electric fields were simulated, targeting RMF. Results: For segmented brain volumes, significant sex differences were observed in the gray matter and RMF, and considerable disease differences were found in cerebrospinal fluid, ventricle, and hippocampus/amygdala complex. There were no differences in the tDCS-induced electric field among AD and normal groups; however, higher peak values of electric field were observed in the female group than the male group. Conclusions: Our findings demonstrated the presence of sex and disease differences in segmented brain volumes; however, this pattern differed in tDCS-induced electric field, resulting in significant sex differences only. Further studies, we will adjust the brain stimulation conditions to target the deep brain and examine the effects, because of significant differences in the ventricles and deep brain regions between AD and normal groups.

• 대한전기학회논문지:시스템및제어부문D
• /
• 제55권10호
• /
• pp.458-463
• /
• 2006

The purpose of this work is to investigate the fundamental properties of the gradual muscle force potentiation. We investigated the dependence of force potentiation on both the pulse-amplitude and the pulse-duration with different ramp-up time. The experimental results showed that the force increment ratio (FIR) during constant electrical stimulation decreased with pulse-amplitude and also with pulse-duration. The FIR was greater with short ramp-up time in both the pulse-amplitude and pulse-width modulation. The feasible mechanism might be that the myosin light chain phosphorylation induces the force potentiation and it occurs only in the fast type muscle fibers which are recruited first. These observations indicate that muscle potentiation must be understood well for the accurate control of muscle force.

• The Journal of Korean Physical Therapy
• /
• 제15권4호
• /
• pp.442-454
• /
• 2003

The aim of this study was to demonstrate the effects of silver spike point (SSP) low frequency electrical stimulation on plasma vasoactive intestinal polypeptide (VIP) activities measured by radioimmunoassay from volunteer and the effects of VIP on pain substance-induced contraction investigated by isometric tension methode in animal. The current of 3 Hz continue type, but not 100 Hz continue type, of SSP low frequency electrical stimulation significantly increased in plasma VIP from normal volunteer. The pain substance, such as norepinephrine, serotonin, and prostaglandin $F2{\alpha}$, increased vascular smooth muscle contraction, respectively. These responses were inhibited by VIP applied cumulatively (1 nM - $1\;{\mu}M$), but not serotonin-induced contraction. In addition, serotonin, and prostaglandin $F2{\alpha}$ induced uterine smooth muscle contraction from rat. However, these responses were inhibited by VIP ($1\;{\mu}M$), only serotonin-induced contraction. These results suggest that the VIP regulates pain substance in part and that the SSP low frequency electrical stimulation, specifically current of 3 Hz continue type, significantly increases plasma VIP from volunteer.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
• /
• pp.318-318
• /
• 2011

Electrosurgery has been widely used in surgical procedures for many years. The surgical procedure using radiofrequency power generated occasionally sparks causing electrical stimulations. According to a paper of commercialized APC (Argon Plasma Coagulation) in the gastrointestinal endoscopy, Patients treated by APC had experienced pain and neuromuscular stimulation. This study aimed to investigate the electrosurgery sparks. In this experiment, current threshold of electrosurgery using rf was investigated. Sparks analogous to surgical situation was generated and measured the I-V figure. Asymmetric current, observed by other researchers, was also measured. This could be explained by difference between positive phase and negative phase. Furthermore, a method was developed to remove asymmetric current and to make safer device for surgical field.

• Journal of Magnetics
• /
• 제19권1호
• /
• pp.20-27
• /
• 2014

This study examined the relationships between protein expression and Poly ADP ribose polymerase in brain cell death in brains damaged by thrombotic stroke and treated with the Full Wave- Cockroft Walton (FWCW) method of Transcranial Magnetic Stimulation (TMS). The two-way switching element for TMS drove a half-bridge inverter of the current resonance of direct current voltage (+) and direct current voltage (-), and the experiment was conducted by stimulating the mice with thrombotic stroke through a range of pulses. Thrombotic stroke was caused of ligation of the common carotid artery of male SD mice, and blood reperfusion was conducted five minutes later. Protein expression was examined in immune reaction cells, which reacted to an antibody to Poly ADP ribose polymerase in the cerebrum cells, and western blotting. Observations of the PARP changes after thrombotic stroke showed that the number of Poly ADP ribose polymerase reactions were significantly lower (p < 0.05) in the group treated with TMS of the FWCW than the group with thrombotic stroke 24 hours after its onset. The application of FWCW-TMS helped prevent the necrosis of nerve cells and might prevent the brain damage that occurs as a result of thrombotic stroke, and improve the function recovery and disorder of brain cells.

• 대한임상전기생리학회지
• /
• 제2권1호
• /
• pp.1-8
• /
• 2004

This study was conducted to assess the effect of transcutaneous electrical nerve stimulation(TENS) and interferential current(IFC) in the patients with myofascial pain syndrome(MPS) on upper trapezius. Twenty patients with MPS on upper trapezius was assigned randomly to TENS group(n=10), IFC group(n=10). In TENS group, TENS was applied to the trigger point. In IFC group, IFC was applied to the trigger point. Duration of treatment was 2 weeks. Effects were assessed before treatment, post treatment by visual analogue scale(VAS), and pain rating score(PRS). Significant change of VAS was noticed in TENS group and IFC group. Significant change of PRS was noticed in TENS group and IFC group. IFC groups were significantly higher than TENS group that of the VAS and PRS. These result showed that IFC is effective treatment method for pain control in patients with MPS.

• The Journal of Korean Physical Therapy
• /
• 제26권6호
• /
• pp.386-390
• /
• 2014

Purpose: We aimed to investigate whether visuomotor function would be modulated, when healthy subjects performed tracking task after tDCS application over the primary sensorimotor cortex (SM1) in the non-dominant hemisphere. Methods: Thirty four right-handed healthy participants were enrolled, who randomly and evenly divided into two groups, real tDCS group and sham control group. Direct current with intensity of 1 mA was delivered over SM1 for 15 minutes. After tDCS, tracking task was measured, and their performance was calculated by an accuracy index (AI). Results: No significant difference in AI at the baseline between the two groups was observed. The AI of the real tDCS group was significantly increased after electrical stimulation, compared to the sham control group. Two way ANOVA with repeated measurement showed a significant finding in a large main effects of time and group-by-repeated test interaction. Conclusion: This study indicated that application of the anodal tDCS over the SM1 could facilitate higher visuomotor coordination, compared to sham tDCS group. These findings suggest possibility that tDCS can be used as adjuvant brain modulator for improvement of motor accuracy in healthy individuals as well as patients with brain injury.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2009년도 추계학술대회
• /
• pp.521-524
• /
• 2009

신경자극반응 측정 플랫폼을 구현하는데 있어서 손가락 움직임을 감지하는 것이 중요한 요소로 작용하고 있다. 이것은 손가락의 움직임에 따라 신경자극과 근육반응이 달라지기 때문이다. 즉, 손가락의 움직임을 감지해서 신경 자극 Actuator 및 근육 반응 감지를 위한 H/W 개발이 필요한 것이다. 또한 임베디드 기반으로 가기위한 저전력 CPU를 사용하였다. H/W 구성은 isolation power부분, 정전류조절, High impedance INA, 증폭기부분이 있으며 Micro-controller에서는 stimulus mode 및 Current 의 상태를 통제하고, AD converter를 통해 얻어진 Low Data를 처리 시스템을 구현한다.

• The Journal of Korean Physical Therapy
• /
• 제31권5호
• /
• pp.328-332
• /
• 2019

Purpose: This study examined the effects of transcranial direct current stimulation (tDCS) on the static balance ability of patients with back pain. Methods: The subjects comprised of 30 males and females in their 20s, who were divided into two groups with and without tDCS. The balance posture ratio score was calculated to determine the changes in balance ability before and after the application of tDCS using balance equipment. A paired t-test was conducted to determine the changes over time, and an independent t-test was performed to determine the changes between the groups. The significance level was set to ${\alpha}=0.05$. Results: A significant difference in the changes in the static balance ability of CTDCSG between before and after applying tDCS was observed while the subjects' eyes were open (p<0.05). A comparison between the groups after the experiments revealed significantly increased changes in CTDCSG compared to STDCSE (p<0.05). The changes in static balance ability were not significant when the subjects' eyes were closed (p>0.05). Conclusion: The application of tDCS positively changed the static balance ability of patients with back pain. The results of this study showed that tDCS could be used as an intervention to increase the static balance ability of patients with back pain in the clinical field. The study results could be used further as foundational data for future studies on tDCS.