• Science of Emotion and Sensibility
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• v.14 no.4
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• pp.537-544
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• 2011

Tactile acuity was assessed in groups of control, blind, deaf, and blind caused by complication to investigate the effective tactile stimuli on tactile sensory substitution studies when tactile display is applied to persons with sensory loss of vision or hearing. Two-point discrimination and grating resolution were assessed by compass and JVP dome, respectively, in the hand, arm, neck, lumbar, and knee. In two-point discrimination by compass, control group showed the highest sensitivity in fingers among assessed body areas but did not show any significant difference between male and female. Blind group and deaf group compared to control group did not show any significant difference in fingers but showed lower sensitivity in arm and knee. In grating resolution by JVP dome, control group did not show any significant difference among five fingers as well as between male and female. Blind group showed higher sensitivity in five fingers compared to control group, but deaf group did not show any significant difference from control group. Blind caused by complication group showed lower sensitivity in two-point discrimination and grating resolution compared to control group and blind group. These results suggest that the body area and method of tactile stimulation, and difference in tactile acuity depending on underlying disease of sensory loss should be considered when tactile display is applied for sensory substitution.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.1
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• pp.9-19
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• 1998

The present study was primarily carried out to characterize the properties of the spinomesencephalic tract (SMT) neurons that project from the upper cervical spinal segments to the midbrain. It was also investigated whether these neurons received convergent afferent inputs from other sources in addition to cervical inputs. Extracellular single unit recordings were made from neurons antidromically activated by stimulation of midbrain. Recording sites were located in lamina $I{\sim}VIII\;of\;C1{\sim}C3$ segments of spinal cord. Receptive field (RF) and response properties to mechanical stimulation were studied in 71 SMT neurons. Response profiles were classified into six groups: complex (Comp, n=9), wide dynamic range (WDR, n=16), low threshold (LT, n=5), high threshold (HT, n=6), deep/tap (Deep, n=10), and non- responsive (NR, n=25). Distributions of stimulation and recording sites were not significantly different between SMT groups classified upon their locations and/or response profiles. Mean conduction velocity of SMT neurons was $16.7{\pm}1.28\;m/sec$. Conduction velocities of SMTs recorded in superficial dorsal horn (SDH, n=15) were significantly slower than those of SMTs recorded in deep dorsal horn (DDH, n=18), lateral reticulated area (LRA, n=21), and intermediate zone and ventral horn (IZ/VH, n=15). Somatic RFs for SMTs in LRA and IZ/VH were significantly larger than those in SDH and DDH. Five SMT units (4 Comps and 1 HT) had inhibitory somatic RFs. About half (25/46) of SMT units have their RFs over trigeminal dermatome. Excitabilities of 5/12 cells and 9/13 cells were modulated by stimulation of ipsilateral phrenic nerve and vagus nerve, respectively. These results suggest that upper cervical SMT neurons are heterogenous in their function by showing a wide range of variety in location within the spinal gray matter, in response profile, and in convergent afferent input.

• Journal of Biomedical Engineering Research
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• v.38 no.2
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• pp.57-61
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• 2017

The purpose of this study was to investigate the effect of direction (pitch and roll) on the perception of support surface rotation while standing. Thirty young healthy subjects participated in this study. Support surface was rotated at an unexpected instant in a very slow speed (0.2 deg/s). The direction of support surface rotation was randomly chosen among pitch (forward and backward) and roll (right and left) directions. The experiment was performed with eyes open and closed. Perception performance was evaluated by the perception threshold, defined as the rotation angle of the surface at the instant when a subject recognized that the support surface was moving. Results showed that the perception threshold was smaller for roll directions than pitch directions irrespective of vision and gender (p < 0.01). This indicates that the perception of support surface rotation is more sensitive in roll direction than in pitch direction. Among three sensory functions related to postural perception, the effect of vestibular and visual functions on the direction difference of the perception should be little because of the very slow surface rotation and independence on visual conditions. Therefore, the direction dependence of perception would have been affected mainly by the somatosensory function.

• PNF and Movement
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• v.18 no.2
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• pp.173-182
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• 2020

Purpose: The purpose of the study was to investigate the effects of visual feedback exercise (VFE), sandal exercise (SE), and thera-band exercise (TE) on people with functional ankle instability. Methods: The 45 study participants were divided into three groups of 15. In the VFE group, participants performed short-foot exercises using visual feedback; the SE group performed sandal exercises, and the TE group performed thera-band exercises. Over a period of 8 consecutive weeks, the experimental groups exercised for 15 minutes per session, four times per week. Balance was measured using the Biodex Balance System for dynamic balance ability (overall balance index [OBI], mediolateral balance index [MBI], and anterioposterior balance index [ABI]). Vibration threshold sense (VTS) was assessed using a vibratory sensory analyzer. Ankle muscular strength was measured using the Biodex 4 Pro. The main outcome measures were assessed at baseline and after 8 weeks of training. Results: Significant improvements in dynamic balance were noted in all three groups (p < 0.05). Significant improvements in VTS and muscular strength were also noted in the VFE and TE groups but not in the SE group (p < 0.05). Conclusion: Appropriate environmental and situational mediation may be of great clinical significance for patients suffering from chronic ankle instability. It is hoped that the findings will inform a program for prevention of ankle instability.

• The Korean Journal of Physiology
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• v.24 no.2
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• pp.305-317
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• 1990

The present study was performed to investigate modification in the electrophysiological characteristics of cat dorsal horn cells during neurogenic inflammation induced by mustard oil. The results obtained were summarized as follows: 1) Following subcutaneous injection of mustard oil the majority of wide dynamic range (WDR) cells (10/15 units) showed enhanced responses (80%) to brush, while the responses to all types of mechanical stiumli were enhanced in 3/15 units. One cell was further activated by pinch and the another was not affected at all after induction of inflammation. 2) The sensitization of WDR cell was resulted from subcutaneous injection of mustard oil either inside or outside of the receptive field (RF), whereas the spontaneous activity increased only after mustard oil was injected inside of the RF. 3) In the animal with inflammation the responses of high threshold (HT) cell to noxious stimulus were not altered, while HT cell responded to such mechanical stimulus as pressure which was usually ineffective in normal animals. 4) After induction of inflammation, low threshold (LT) cell appeared to be converted to WDR cell, showing responses not only to brush but also to pressure and pinch. 5) The mustard oil-induced inflammation enhanced responses of WDR and HT cells to the thermal stimuli and also resulted in a pronounced after-discharge in WDR cells. 6) After subcutaneous injection of lidocaine, the increased background activity of WDR cells due to inflammation was almost completely abolished. 7) A subcutaneous injection of mustard oil inside of the RF invariably desensitized the dorsal horn cells which receive sensory inputs from the inflamed RF. From the results of Present study it was revealed that a neurogenic inflammation induced by mustard oil resulted in an enhancement of responses of cat dorsal horn cells to mechanical and thermal stimuli.

• Analytical Science and Technology
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• v.16 no.3
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• pp.240-248
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• 2003

Sulfur compounds which are well-known odor-active compounds in industrial area have very low detection threshold values. Trace amounts of volatile sulfur compounds in enviroment air around several odor sources were concentrated in liquid argon bath and determined by gas chromatograph with flame photometric detector (FPD) which exhibits very good selectivity and sensitivity. 25% ${\beta}$,${\beta}$-Oxydipropionitrile on 60/80 Chromosorb W was used as adsorbent for the preconcentration of sulfur compounds in air sample and also as packing material for a packed glass column. Concentration volume of air sample was different from place to place in the range of 0.1~3.0L. Atmospheric concentrations of sulfur compounds in air of residential districts and boundaries of business establishments, and also those in the exhausted gases of emission points such as a sewage disposal plant in industrial area were measured.

• Diabetes and Metabolism Journal
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• v.42 no.6
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• pp.519-528
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• 2018

Background: Clinical manifestations of diabetic peripheral neuropathy (DPN) vary along the course of nerve damage. Nerve conduction studies (NCS) have been suggested as a way to confirm diagnoses of DPN, but the results have limited utility for evaluating clinical phenotypes. The current perception threshold (CPT) is a complementary method for diagnosing DPN and assessing DPN symptoms. We compared NCS variables according to clinical phenotypes determined by CPT measurements. Methods: We retrospectively enrolled patients with type 2 diabetes mellitus who underwent both NCS and CPT tests using a neurometer. CPT grades were used to determine the clinical phenotypes of DPN: normoesthesia (0 to 1.66), hyperesthesia (1.67 to 6.62), and hypoesthesia/anesthesia (6.63 to 12.0). The Michigan Neuropathy Screening Instrument (MNSI) was used to determine a subjective symptom score. DPN was diagnosed based on both patient symptoms (MNSI score ${\geq}3$) and abnormal NCS results. Results: A total of 202 patients (117 men and 85 women) were included in the final analysis. The average age was 62.6 years, and 71 patients (35.1%) were diagnosed with DPN. The CPT variables correlated with MNSI scores and NCS variables in patients with diabetes. Linear regression analyses indicated that hypoesthesia was associated with significantly lower summed velocities and sural amplitudes and velocities, and higher summed latencies, than normoesthesia. Sural amplitude was significantly lower in patients with hyperesthesia than in patients with normoesthesia. Conclusion: NCS variables differed among patients with diabetes according to clinical phenotypes based on CPT and decreased sural nerve velocities was associated with hyperesthesia.

• Journal of Korean Physical Therapy Science
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• v.2 no.3
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• pp.599-608
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• 1995

If a controlled sensory stimulation is given to the specific receptors, a reflex movement and motor engrams is achieved by the principle of neurophysiology. Based on this theoretical background, we choose 80 healthy person(male 40,female 40) and compare chronaxie of before stimulation with after stimulation. Also we measured chronaxie with same method. Stimulation was applied to the muscle belly by tapping. The results are summarized as follows; 1. The mean value of rheobase measured from the proximal part of upper extremity is 3. 56mA for male, 4.04mA for female. 2. The mean value of rheobase measured from the lower extremity is 4.19mA for male, 4. 37mA for female, which is higher than that of upper extremity for both male and female. 3. The mean value of chronaxie from the proximal part of upper extremity is 0.91msec for male, 0.87 msec for female, which means male is higher than female, and the average is 0.82msec. 4. The mean value of chronaxie from the proximal part of lower extremity is 1.04msec for male, 1.14msec for female, which means female is higher than male. 5. The decrease of rheobase after stimulation is prominent at the triceps brachii for male, biceps brachii for female. 6. The decrease of rheobase after stimulation is prominent at the tibialis anterior for both male and female. 7. The decrease of chronaxie after stimulation is prominent for both male and female at the triceps brachii from upper extremity and at the tibialis anterior from lower extremity for both male and female.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.37-43
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• 1991

The nerve impulse pattern of Chorda tympani(CT) of cat was tested with Monosodium glutamate(MSG) solutions as well as some basic taste substances applied on the tongue of cat. The effect of MSG applied in the tongue prior to the stimulation of other taste substances was also investigated. The response impulse frequency of CT of cat was changed by the kind and concentration of taste substances. The response to citric acid was the highest among the tested substances, NaCl, KCl and MSG showed similar responses. When different concentrations of MSG were applied on the tongue prior to other substances, the response to NaCl increased with the maximum response at the MSG concentration of 0.02 M. The response to sucrose tended to be reduced, but the response to citric acid was distinctly supressed by the previous MSG stimulation. These results were well consistent with the sensory evaluation on the effect of MSG to some basic taste substances. previously reported by the authors.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.1
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• pp.35-45
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• 1999

Excitatory amino acid (EAA) and substance P (SP) have been known to be primary candidates for nociceptive neurotransmitter in the spinal cord, and calcium ions are implicated in processing of the sensory informations mediated by EAA and SP in the spinal cord. In this study, we examined how $Ca^{2+}$ modified the responses of dorsal horn neurons to single or combined iontophoretical application of EAA and SP in the rat. All the LT cells tested responded to kainate, whereas about 55% of low threshold (LT) cells responded to iontophoretically applied NMDA. NMDA and kainate excited almost all wide dynamic range (WDR) cells. These NMDA- and kainate-induced WDR cell responses were augmented by iontophoretically applied EGTA, but suppressed by $Ca^{2+},\;Mn^{2+},$ verapamil and ${\omega}-conotoxin$ EVTA, effect of verapamil being more prominent and well sustained. $Ca^{2+}$ and $Mn^{2+}$ antagonized the augmenting effect of EGTA. On the other hand, prolonged spinal application of EGTA suppressed the response of WDR cell to NMDA. SP had triple effects on the spontaneous activity as well as NMDA-induced responses of WDR cells: excitation, inhibition and no change. EGTA augmented, but $Ca^{2+},\;Mn^{2+}$ and verapamil suppressed the increase in the NMDA-induced responses and spontaneous activities of WDR cells following iontophoretical application of SP. These results suggest that in the spinal cord, sensory informations mediated by single or combined action of EAA and SP can be modified by the change in calcium ion concentration.