Analysis method for psychological and physiological responses to body massage "Using POMS and HRV".

This study aimed to compare and proposed an analytical method for evaluating the effectiveness of massage using various measurement parameters. The parameters were divided psychologically using the Profile of Mood States (POMS) and physiologically using heart rate variability. In the experiment, the psycho-physiological effects of the rest(a) and two massage techniques (b, c) were evaluated. The effect of each massage technique on the parameters was examined, and a statistical analysis approach for evaluating massage responses is given in the conclusion.Clinical Relevance- This case study compares and contrasts the differences and advantages of each statistical approach for analyzing on studying the effects of massage and presents the response results for two massage techniques.

Ability of ergonomic timeout to reduce musculoskeletal discomfort related to fluoroscopic endoscopy.

Endoscopists performing fluoroscopy procedures often suffer from musculoskeletal disorders (MSDs) due to persistent static muscle contraction and the load imposed by radiation personal protective equipment. We devised the "practical load-on-the-shoulders releasing technique" (PoRT), integrated it within the work-rest schedule, and investigated its ability to reduce muscular discomfort. The results showed that PoRT lowered discomfort, including by maintaining the head angle closer to the neutral position and keeping the trunk in a stable state, which together resulted in an ideal posture. As a simple, no-cost intervention based on an ergonomic approach, PoRT may contribute to reducing MSDs.

Change Detection of Sleeping Conditions based on Multipoint Ambient Sensing of Comforter on Bed.

This paper describes a method for the detection of changes in sleeping conditions using multipoint ambient sensing for safety and amenity in the sleep environment. This method continuously detects changes during sleep, such as the movements of the person and bedding based on the measurement of acceleration, temperature and humidity of the comforter. Through the measurement of these ambient conditions, this system improves sleep quality and prevents accidents, such as falling off the bed. In this study, a basic system using internet of things (IoT) devices is constructed, and performance verification is conducted. The experimental results show the feasibility of the proposed method.

Evaluation of nocturnal heart rate variability for strenuous exercise day using wearable photoelectric pulse wave sensor.

In this study, we examined whether or not the strenuous exercise in the evening change nocturnal heart rate variability (HRV) and recovers. Subjects were 8 healthy men belonging to the mature futsal team (age: 35±3 years) and Futsal was held from 5:00 p.m. to 6:30 p.m. on Sunday. Pulse waves during sleeping were measured at home on exercise day and on control day. The mean pulse interval (MPI), standard deviation pulse interval (SDPI), low frequency component (LF, 0.04-0.15 Hz), high frequency component (HF, 0.15-0.45 Hz) and the ratio of LF to HF (LF/HF) were calculated from pulse interval time series every 30 min. As a result, MPI, SDPI, LF, HF of exercise day were significantly lower than control day (P<0.0001). LF/HF of exercise day was significantly higher than control day (P<0.05). Regarding change of HRV for every 30 min, MPI (P<0.05), SDPI (P=0.0003), LF (P=0.0038), HF (P<0.05) were observed significant changes. MPI and HF before wake-up did not reach the level of control day. It is thought that strenuous exercise in the evening promotes sympathetic nervous activity during night sleep and suggesting that pulse rate and HRV have not recovered by the wake-up time.

Proprioceptive change impairs balance control in older patients with low back pain.

[Purpose] This study aims to determine the specific proprioceptive control strategy used during postural balance in older patients with low back pain (LBP) and non-LBP (NLBP) and to assess whether this strategy is related to proprioceptive decline and LBP. [Subjects and Methods] Pressure displacement center was determined in 47 older persons with LBP and 64 older persons with NLBP during upright stance on a balance board without vision. Gastrocnemius (GS) and lumbar multifidus muscle (LM) vibratory stimulations of 60 and 240-Hz, respectively, were applied to evaluate the relative contributions of different proprioceptive signals (relative proprioceptive weighting ratio, RPW) used in postural control. Age, height, weight, back muscle strength, L1/2 and L4/5 lumbar multifidus cross section area ratio, skeletal muscle mass index, sagittal vertical axis, and Roland-Morris disability questionnaire (RDQ) were evaluated. [Results] Compared with older patients with NLBP, those with LBP showed a lower RPW 240-Hz, lower L4/5 lumbar multifidus cross-sectional area ratio, and a significantly higher age and RDQ. Logistic regression analysis showed that RPW 240-Hz and age were independently associated with LBP, after controlling for confounding factors. [Conclusion] Older patients with LBP decreased their reliance on GS (RPW 240-Hz) proprioceptive signals during balance control.

Study on improvement of signal detectability considering noise characteristics in medical X-ray images.

The purpose of this study is to develop method for improvement of low-contrast signal detectability of general X-ray images used for observing overviews, included noise reduction technique and signal amplification technique, that are difficult to detect in the observing overview. The proposal method consists signal amplification part and noise reduction part. The noise reduction part first identifies and mathematizes the characteristics of the noise attributed to the X-ray imaging system before the subject is imaged. The noise information derived from mathematization is used to remove the noise representing the system noise from the subject image. After noise reduction, all the signals on the subject image with sufficiently reduced noise are amplified by multiplication with an arbitrary coefficient. The feasibility of the proposed method was indicated by three evaluations that were performed vision assessment using the image including the virtual low-contrast signals by four radiological technologists. That of the proposed method was confirmed from results of the evaluations. That of the proposed method was confirmed from results of the evaluations.

Preventing drowsiness by heartbeat-synchronized vibration.

The purpose of this study is to develop a stimulation, which has an active physiological influence to prevent severe driver drowsiness while driving. This paper presents a heartbeat-synchronized vibration, which is the rhythmic pulsation of a motor with each beat of the heart, as an effective means to ease drivers' slight deprivation of oxygen with the appearance of cardiorespiratory coordination. The effects of this stimulation were confirmed by the results of an experiment done in cooperation with 15 subjects. The results showed that cardiorespiratory coordination appeared under the stimulation and it played an active influence on the oxygen supply to the body. We conclude that the vibratory stimulation has an active influence to prevent drowsiness. It might be effective to prevent severe drowsiness while driving.

[Analysis of electrogastrography in gastrectomized subjects].

OBJECTIVES: To establish a method for the development of a mathematical model of autonomic activity in gastrointestinal movements and to basically evaluate of the application of the nonlinear analysis method to electrogastrography, we performed feature extraction of electrogastrographic changes in healthy elderly and gastrectomized subjects. METHODS: The subjects consisted of 9 healthy elderly males and 3 elderly males without constipation who had undergone resection of 2/3 of the stomach. Electrogastrograms were obtained in a sitting position for 30 minutes and in a supine position for 90 minutes. Spectrum analyses of electrographic time series, the maximum Lyapunov exponent for the evaluation of the chaos of dynamic systems forming time series, and translation error for the evaluation of the smoothness of the attractor orbit were performed. RESULTS: The maximum Lyapunov exponent was a positive number in all analysis intervals in all subjects. This suggests the irregularity of electrogastrograms in gastrectomized subjects. The translation error in the gastrectomized subjects was higher than that in the healthy elderly subjects, showing irregularity. However, as a result of spectrum analysis, gastric electric activity was predominant on electrogastrograms of the healthy elderly subjects, but intestinal electric activity was predominant in the gastrectomized subjects. CONCLUSIONS: Differentiation between healthy and gastrectomized elderly people is difficult using only one of the spectrum analysis methods, the maximum Lyapunov exponent, or the translation error. However, since the extracted features differed among the 3 analysis methods, differentiation and diagnosis may be possible using a combination of these methods.

Optimum arousal level preservation system using biosignals.

The purpose of this study is to develop a driver's optimum arousal level preservation system while driving. The important point of developing this system is how we keep a driver's adequate conditions on driving. Most of the systems, which have been already put to practical use, are using audible sound or warning messages on a display to urge driver to take a rest. However, arousal levels are strongly related to the balance of autonomic modulations; therefore we need the stimulation that preserves a driver's adequate condition physiologically. Some preceding studies reported that the stimulation using the biological rhythms especially heart beating rhythms are influential to human body. We gave a consideration to this fact and made a course of using driver's heartbeat rhythm for the feedback stimulation to realize the demand. In this paper, we examined the stimulation from two points of views. The one is to investigate the possibilities of controlling a driver's heartbeat rhythms by making synchronization between the driver's heartbeat and a vibratory stimulation. The other one is to find out the stimulation that induces RSA (Respiratory Sinus Arrhythmia) in order to adjust the parasympathetic modulations. The result of the experiment indicated that the 1 [s] constant beat stimulation has an effect of inducing RSA, and the stimulation using a rhythm of heartbeat has a possibility of controlling driver's heart rate variability, and its' efficiency might be possible to be improved by adjusting the rhythm of the stimulation to the driver's heartbeat rhythms.

Development of a feedback stimulation for drowsy driver using heartbeat rhythms.

We investigated the physiological response of a vibratory stimulation, which has the rhythm of heartbeats, and examined whether it is useful for the feedback stimulation for drowsy driving. We evaluated the efficiency of 4 types of vibratory rhythms for stimulation by using the sleepiness level estimated by the multiple linear regression model made from the indices of ECG and respiration. As the result, the vibratory rhythm, which has the real time heartbeats of subjects themselves, had an effect of inducing their physiological condition closer to the condition when they were struggling against the drowsiness. We concluded that the stimulation might be useful to prevent a drowsy driving if we could give it to the driver before he or she gets the severe drowsiness.

Visualizing physiological condition of two persons during cooperative motion.

The purpose of this study is to develop a visualizing system which represents human motion and physiological conditions such as muscle activities, autonomic nervous balances of multi persons simultaneously. Our system generates avatar animation representing muscle activity and heart rate variability of multi persons by color of muscles and heart. Three kinds of assistance motion were visualized to evaluate our system. In these experiments, muscle activity and heart rate variability of assisted and service persons were represented. Physiological conditions of multi persons are presented intuitively using this system. This visualizing system is useful for analysis of workload in cooperative motion.

Real-time continuous estimation of respiratory frequency during sleep based on heart rate time series.

It is reported that frequency component (RSA) of approximately 0.25Hz of heart rate time series is corresponding to the respiratory frequency. In this paper, we proposed the continuous estimation method of respiratory frequency during sleep using the number of extreme points of heart rate time series in real time. Procedure for calculation of the method is very simple. Frequency of RSA was calculated using the proposed method from the heart rate time series during supine rest and during sleep. It is considered that the proposed method can be applied to respiratory monitoring system during sleep.

Development of health monitoring system based on three-dimensional imaging using bio-signals and motion data.

The purpose of this study is to develop a health monitoring system. This system represents human health condition and human motion simultaneously. This system obtains motion data by optical motion capture system. Electromyogram and electrocardiogram are used for health condition estimation. These are measured synchronously with motion data. Two experiments were performed to evaluate our system. In these experiments, muscle activity, motion of the heart and the autonomic nervous balance were represented as health conditions. This system contributes intuitive recognitions of health condition and high accurate estimation of health conditions.

Estimation of bio-signal based on human motion for integrated visualization of daily-life.

This paper describes a method for the estimation of bio-signals based on human motion in daily life for an integrated visualization system. The recent advancement of computers and measurement technology has facilitated the integrated visualization of bio-signals and human motion data. It is desirable to obtain a method to understand the activities of muscles based on human motion data and evaluate the change in physiological parameters according to human motion for visualization applications. We suppose that human motion is generated by the activities of muscles reflected from the brain to bio-signals such as electromyograms. This paper introduces a method for the estimation of bio-signals based on neural networks. This method can estimate the other physiological parameters based on the same procedure. The experimental results show the feasibility of the proposed method.

Heart rate indication using musical data.

Heart rate data reflects various physiological states such as biological workload, stress at work and concentration on tasks, drowsiness and the active state of the autonomic nervous system. This paper proposes system to indicate heart rate using musical data. Music changes physiological states for the better by relaxing people, or contributing to patient treatment through music therapy. Information in the form of music is advantageous because it does not hinder work as does verbal information and it contains more information than warning noises. We introduce and evaluate a prototype heart rate indication system and describe evaluation results of biofeedback effects on the worker during mental workload. The prototype system sequentially inputs the instantaneous heart rate into the computer, converts the data into musical instrument digital interface, the digital music format, and outputs it from the sound source.