Faculty Profiles - NAKAMURA Takao

Consideration to Impedance Pharyngography (IPG) of Swallowing Disorders

Measurement and evaluation of swallowing in subject with advanced age or swallowing disorders by impedance pharyngography

NAKAMURA Takao, KUSUHARA Toshimasa, MORI Keiko, YAMAMOTO Yoshitake

16 75 - 78 2001.8

KUSUHARA Toshimasa, NAKAMURA Takao, MORI Keiko, YAMAMOTO Yoshitake

IEICE technical report. ME and bio cybernetics 101 ( 181 ) 91 - 96 2001.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

Swallowing disorders are a serious problem occurring in nerve or muscle disease, advanced age and so on. Unfortunately, it is difficult to evaluate swallowing disorders quantitatively. For this reason, we previously proposed a new method, impedance pharyngography(IPG), for evaluating swallowing disorders quantitatively and noninvasively by measuring neck electrical impedance during swallowing. In this study, the efficacy of this method was tested in a cohort of patients and advanced age, not only healthy subjects who were once measured mainly. And we have considered characteristics of each subject's result of IPG measurement.

Other Link： http://search.jamas.or.jp/link/ui/2002051760

局所インピーダンス計測のための多重同心電極の開発

山本尚武, 中村隆夫, 磯崎晃一, 白井喜代子, 奥田博之

日本ME学会大会論文集 40th 2001

頚部電気インピーダンスを用いたほ乳動作計測の基礎的検討

中村隆夫, 津川英範, 山本尚武, 合田典子, 奥田博之

日本ME学会大会論文集 40th 2001

Variations of parameters of bioelectrical impedance during biodynamics

NAKAMURA Takao, YAMAMOTO Yoshitake

IEICE technical report. ME and bio cybernetics 100 ( 190 ) 1 - 7 2000.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

Variations of human limb electrical impedance during biodynamics were caused by variations of equivalent cross sectional area of muscle and variations of blood volume. In this work, we explained variations of the impedance with variations of parameters of an equivalent circuit. The equivalent circuit consisted of five individual parameters as follows: extracellular fluid resistance, 'R_e', intracellular fluid resistance, 'R_i', characteristic frequency of dispersion, 'f_m' and parameters of dispersion of relaxation time, 'α' and 'β'. Impedances of forearm and upper arm were measured during flexion and extension of joints in upper limb. The equivalent series resistance R was strongly influenced by R_e and R_i. In case of the maximum flexion of the elbow joint, R of upper arm was influenced f_m. This means that a polarization of cell membrane changes and influences impedance during movement.

Modeling of Electrodermal Activity

Other Link： http://search.jamas.or.jp/link/ui/2001036498

TAKAYAMA Keiichi, ISOSAKI Kouichi, YAMAMOTO Yoshitake, NAKAMURA Takao

IEICE technical report. ME and bio cybernetics 99 ( 688 ) 85 - 90 2000.3

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

Electrodermal sctivity (EDA) is one of parameters which show a mind activity condition. EDA has been used for a polygraph or early detection and early treatment of mental disorder for many years. EDA is also used for image training of sports players these days. Although the applications of EDA have made advances, the mechanismof EDA is not sufficiently made clear. In this study, we measured skin potential and skin impedance simultaneously, and proposed an EDA model cosidering changes of skin potential and skin impedance. We confirmed the validity of the model using a simulation.

Other Link： http://search.jamas.or.jp/link/ui/2000231091

Analysis of Swallowing Using Swallowing Sound

TSUGAWA Hidenori, YAMAMOTO Yoshitake, NAKAMURA Takao

IEICE technical report. ME and bio cybernetics 99 ( 178 ) 31 - 36 1999.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

It is an aging society and people complaining of swallowing trouble have been increasing. We proposed a new method using swallowing sound to diagnose swallowing trouble. The method is simple and noninvasive. We examined reproduction and difference of swallowing sound which is due to kinds of food. And we examined the relation between swallowing sound and IPG (Impedance Pharyngography) using the neck electrical impedance.

Estimation of the Ankle Angle Using Leg Electrical Impedances

Other Link： http://search.jamas.or.jp/link/ui/2000027039

SUKO Toshiyuki, YAMAMOTO Yoshitake, NAKAMURA Takao

IEICE technical report. ME and bio cybernetics 98 ( 174 ) 23 - 30 1998.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

Untill now, we have estimated the change of the ankle joint angle using calf impedance. The purpose of this report is to estimate the ankle angle during walking using thigh impedance and calf inpedance. First, we compared an estimation using the calf impedance only with an estimation using the thigh impedance and the calf inpedance. We confirmed that the estimation using two impedances was higher precise than the other. In cases of estimation of the ankle joint angle during walking, the calf impedance is influenced by the ankle joint moment with the floor reaction force. Therefore, we investigated relationships between the floor reaction force and the calf impedance. Considering the results, we estimated the ankle joint angle during walking using three parameters, which were the thigh impedance, the calf impedance and the floor reaction force.

Swallowing Evaluation Using Parameter Analysis of IPG

KUSUHARA Toshimasa, NAKAMURA Takao, YAMAMOTO Yoshitake, SEKI Yasuhiko, AKASHI Ken, JIKUYA Kazuaki

IEICE technical report. ME and bio cybernetics 98 ( 174 ) 15 - 21 1998.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

We have proposed IPG (Impedance Pharyngography) using the neck electrical impedance for evaluation of swallowing. In this study, we tried parameter analysis in order to establish with the application of IPG to evaluating of swallowing as more effective method. That is to say, we realized relative and quantitative evaluating method by parameter expression which is paid attention to normality, stability and motion of IPG. Further, we analyzed parameter analysis about IPG of young people and elderly, and we examined effectiveness of our method by expressing influence of aging.

Examination on wallowing activity evaluation method by parametric analysis of IPG.

楠原俊昌, 津川英範, 山本尚武, 中村隆夫

電気・情報関連学会中国支部連合大会講演論文集 49th 1998

Electrical and optical characteristics of flowing blood in an artificial vessel with stenosis

NAKAMURA Takao, LINDBERG Lars-Goran, YAMAMOTO Yoshitake, OBERG P. Ake

IEICE technical report. ME and bio cybernetics 97 ( 215 ) 65 - 70 1997.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

The purpose of this study was to investigate the characteristics of light transmission and electrical impedance of flowing blood in an artificial vessel including stenosis. The artificial blood vessel consisted of a rigid flow-through model. The method of impedance measurement used the four-electrodes technique based on sinusoidal current (10 kHz). Light (940 nm) was guided to the model by an optical fiber and transmitted light and was picked up by a similar fiber on the opposite side. Relative change in light transmission and electrical impedance dacreased with increasing blood flow in general. But the relative change in light transmission and electrical impedance varied differently comparing measurements close to the stenosis and at different distances from the stenosis.

Investigation of IPG by Multi Channels Impedance Measurement for Swallowing Evaluation

KUSUHARA Toshimasa, YAMAMOTO Yoshitake, NAKAMURA Takao, SEKI Yasuhiko, AKASHI Ken, JIKUYA Kazuaki

IEICE technical report. ME and bio cybernetics 97 ( 215 ) 31 - 37 1997.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

We have proposed IPG(Impedance Pharyngography) for analysis of swallowing. Now, we discussed about using IPG to improve reliableness and establish diagnosis basis. That is to say, we measured neck electrical impedances simultaneously using IPG measurement application with multi channels. First, we measured IPG and Electroglottography, which using neck electrical impedance like IPG. From the result, we discussed about formative mechanism of IPG and activity of organs which are concerned with swallowing. Next, we specified the organ which is concerned with IPG forming from result of divisional measurement to the front and side of neck.

Investigation of neck electrical impedance during swallowing

Measurement of Neck Electrical Impedance by Multi Channel for Swallowing Analysis.

楠原俊昌, 山本尚武, 中村隆夫, 中桐栄樹

電気学会全国大会講演論文集 1997 ( 1 ) 1997

Examination of organism linearity in multichannel impedance measurement.

楠原俊昌, 山本尚武, 中村隆夫, 椙本憲洋

電気・情報関連学会中国支部連合大会講演論文集 48th 1997

NAKAGIRI Shigeki, YAMAMOTO Yoshitake, NAKAMURA Takao, SEKI Yasuhiko, AKASHI Ken, JIKUYA Kazuaki

IEICE technical report. ME and bio cybernetics 96 ( 150 ) 41 - 48 1996.7

Language：Japanese Publisher：The Institute of Electronics, Information and Communication Engineers

We have measured and discussed a number of neck electrical impedances during swallowing, toward the improvement of reliability and the establishment of diagnostic bases for the swallowing disordered inspection. There are a little variations among the swallowing movements, even if in the same subject. Finst, we have discussed about the influence that the following factors have on impedance waveform : the variations of the swalloing movement, the difference the reappearance of electrodes attaching positions and the influence that the difference among food and drink cause. Next we have also discussed the mechanism of impedance pharyngography in consideration of impedances of smaller measured parts, which are parts of normal measured part, and variations of neck electrical impedance vectors on the impedance plane during swallowing.