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Various kinds of analysis including fast Fourier transform (FFT) were widely used for the classification of electroencephalogram (EEG) based human interfaces. However, the morphological characteristics of EEG waveform were rarely used, since the EEG waveform is thought to show no significant meaning due to its stochastic features. The authors have studied on SSVEP-based BCI for disabled patients. The objective of this study is to verify feasibility of amplitude probability density distribution (APD) used as a feature contributing classification EEG. In this study, the amplitude probability density distribution, which indicated as the index of morphological characteristics of EEG, was applied for state classification using deep learning. CNN was introduced to construct the model of deep learning, classify the obtained data calculated by introduced novel APD method and FFT in order to compare the feasibility. The data were obtained from EEG recorded when subjects were presented flashing light with low stimulus luminosity reversed at 20 and 60 Hz. EEG measurement was conducted in shield room and 9 healthy adulthood male subjects participated in this study. As a result, the case of EEG spectrum by FFT as the control data, the classification accuracy was 85.81%, while using APD yielded 87.98%. The classification accuracy in both analyses showed almost similar result. To conclude, apart from the traditional frequency characteristic, it is feasible in utilization of morphological information in classifying EEG characteristics obtained from two different frequencies. Some problems of implementation for the BCI and efficacy of present method will be discussed.

There has been a lot of researches on the estimation/characterization of human emotions by using communication channels such as facial expressions. However, most of this research has focused on extracting facial features for some specific emotions at specific situations because the difficulty of the general characterization. We have developed a system that can characterize an emotion of an e-Learning user by analyzing his/her facial expression and biometric signals. The criteria used to classify the eight emotions were based upon a time sequential subjective evaluation of emotions as well as a time sequential analysis of facial expressions and biometric signals. The average coincidence ratio between these discriminated emotions by using the criteria of emotion diagnosis and the time sequential subjectively evaluated emotions for ten e-Learning examinees was 71%. When only the facial expressions were observed, the coincidence ratio was 66%. This suggests the multi-modal emotion diagnosis is effectiveness for estimating an e-Learning user's emotions.

The authors have been studying psychophysiological workload of human interface (HI) with physiological measurements and analysis. In this study, we investigated a kind of mental workload produced by user's unexpected waiting period from the request input to the termination of data processing during personal computer (PC) operation. As the experimental setting of HI, we used interactive software containing easy questions with unexpected time interval between each question. The effects of progress indicator (PI) indicating during waiting period on psychophysiological status of users were analyzed by using respiration, finger plethysmogram (PTG), heart rate (HR) and electroencephalogram (EEG) measurements. Results showed that the theta wave component of the EEG increased in the non-PI condition, even though autonomic nervous system parameters showed no significant change. Negative correlation between preference score for HI and integrated theta component percentage was observed only in non-PI condition. It is supposed that the PI was controlling theta activity coused by waiting stress in experimental condition. Utilizing physiological indices for HI assessment, this experimental method could be available to waiting stress estimation.

The aim of this experiment is to evaluate visuospatial and visuomotor cognitive function of the normal healthy young subjects. Estimation of object in motion in blinded spatial environment requires focused attention involving retrospective and prospective memory directly relating to visual cognitive functions. The task was carried out on a computer screen where the subjects followed an object in motion that disappears at specified distance and triggering the stop button when the object reaches a specified target. Blind distance and speed variables were used as criteria to determine the cognitive functions in the subjects. Two groups of five subjects performed a visual motion task with no feedback; namely blind condition (object do not reappears upon target triggering) and with feedback; namely visible condition (object reappears upon target triggering) in the reverse order for each group. Results showed object's longer disappearance duration (wider blind distance) affects deterioration in prospective memory more compared to narrower blind distance and the speed of the object has minimal affect in estimating the target.

In order to develop the effective evaluation system for the fatigue of operator's visual system in long term operation, the experiments were carried out utilizing perceptual time duration of motion aftereffect (MAE), critical flicker frequency (CFF) and the near point (NP) measurement. The MAE was measured using rotated spiral figure displayed on a CRT screen. To generate visual fatigue, a signal detection task in randomly displayed alphabets was used. After the task, MAE duration, CFF and NP were increased. It is supposed that the visual fatigue generated by the experimental task affects motion processing system of visual cortex. Results suggest that the MAE can be an effective tool for visual fatigue evaluation.

We are studying a novel concept of the on-line hospital system using a virtual environment called “Hyper Hospital”. The “Hyper Hospital” is a medical care system which is constructed in a distributed electronic information network using virtual reality (VR) as a human interface. In the present study, physiological and psychological responses of healthy young male subjects were measured by controlled experiments. Some physiological indices such as heart rate, blood pressure, and urinary catecholamine release showed statistically significant differences between results of control experiments using non-VR stimuli and results of VR loading experiments. However they were thought to be mainly from non VR origin. Subjective fatigue was complained by some sujects and they were thought to be indicating a direction of an improvement of our VR system in future. In conclusion, our VR system was proven to be safe when it is used for light medical purpose.

We proposed a novel concept of the on-line hospital system using a virtual reality called “Hyper Hospital”. For making the “Hyper Hospital” come true, it is important to investigate the effect of the virtual reality system (V. R. system) on the human body. In this experiment, twenty healthy young male subjects were exposed to our own V. R. system and their circulatory and respiratory function including blood pressure, ECG, pulse wave, etc., were recorded for 35 minutes. Results showed that the subjects did not experience strong effects on their circulatory and respiratory function by the V. R. system.

We are studying virtual reality system for “Hyper Hospital”. The “Hyper Hospital” is a medical care system which is distributedly constructed on an electronic information network. In the present report, we discussed a new version of our virtual reality system using a head-position sensor by the ultrasound, and a new head mounted display as the hardware parts of the system. We also developed an object oriented software to construct the virtual world for the Hyper Hospital. For severely disabled patients, we are studying the feasibility of the ERP (event related potential of the electroencephalogram) based human interface. The prototype system of the “Hyper Hospital” developed in the present study was shown to be applicable to the real medical environment.

Current situation of therapeutic and diagnostic equipments and their clinical aspects are described. Topics of clinical applications and expected status of regenerative and gene engineering are also reviewed. Contributions of new clinical technology and several low invasive medical equipments are discussed for medical care system in incoming era.

In order to assess psychophysiological state of the hyper arousal, pulse transit time during a mental task was analyzed using the ECG R-wave finger plethysmogram onset asynchrony (RPA) measurement. As the mental task, the authors used the Wisconsin card sorting test (WCST). In the test, the following two kinds of condition were used: (1) a toy balloon burst setting with time limit, and (2) a narrated Japanese novel comprehension test. Under experimental conditions, measured RPAs were shorter than these in control conditions. It is suggested that the RPA is a possible tool for the assessment of hyper arousal through the autonomic responses.

We proposed a new concept of medical care system, named the "hyper hospital" which is constructed in computer based electronic information network. It is built as a distributed system on the network and consists of all kinds of conventional medical care facilities in both the real and the imaginary spaces. The virtual space of the hyper hospital and private information are owned and exclusively controlled by the patient, thus the maximum protection of the privacy of the patients can be observed. In the hyper hospital, an innovative human interface must be required for the consultation, treatment and other communication to the medical staff. This is especially true if the users are of severely disabled patients. The purpose of the present study is to establish a new human interface based on the event related potential, which enables those kind of patients to communicate with others including medical care staffs without any physical actions. >

We proposed in the present study a concept of an online hospital named "Hyper Hospital." The Hyper Hospital is a medical care system which is distributedly constructed on a computer-based electronic network with assistance of an alternate reality system, such as the virtual reality system. First, we reviewed problems of old conventional type of hospital system from viewpoint of human interface, and secondly presented a general idea of the construction of the Hyper Hospital. Lastly, we discussed its applicability and use as a new paradigm of the next generation of medical care. >

The Hyper Hospital is constructed in a computer based electronic network using the virtual reality system as the human-machine-human interface. Most of the physical contact, such as the visit to the out patient office by the patient, is actualized by the electronic connection of the patient private space and the public space of the hospital system. To realize such a system, the authors studied the physiological and psychological responses of healthy subjects induced by the usage of the VR in terms of fatigue. Twenty healthy young male subjects were exposed to the virtual reality system and they performed some psychological tasks with a virtual nurse for 30 minutes. None of the physiological or psychological parameters showed significant fatigue induced by the authors' VR system.

We have been developing a novel medical care system which is constructed on an electronic or computerized information network using virtual reality as the principal human interface. The major purpose of the hyper hospital is to restore humane interactions between patients and various medical caretakers by making a much closer contact between them in the real medical scene than that in current conventional medical practice. In the present study, we discuss the most fundamental part of the development of the virtual reality system for the medical use, that is, system software for the creation of the virtual world which can be defined and modified by users of various levels, not only by the medical caretakers, but particularly by patients.

Publisher Summary This chapter discusses the evaluation of the safety features of a virtual reality (VR) system. Several measures of the physiological, biochemical, neurological, and psychological fatigue are calculated before, during, and after the control experiments. Similar is the case with the VR loading experiments in the study discussed in the chapter. It is found that there is subjective fatigue, particularly related with the psychological condition. The urinary catecholamine release (including epinephrine and dopamine) is found to increase in the VR loading sessions as well as the control video sessions. No increase in the norepinephrine release in the VR experiments are found while it increased in the control video session. Based on this, it is speculated that the use of VR does not have much effect on the physical condition, but may slightly affect the mental or psychological state; however, the extent of this effect is not as severe as the usual video presentation.

Publisher Summary This chapter discusses the general construction, user reconfigurable design, new cybernetic interface, feasibility, and safety features of virtual reality technology as a human interface to networked medical systems. The prototype of the Hyper Hospital described in this chapter has shown that the user reconfigurable virtual reality (VR) world paradigm can be implemented into such a system and can be practically used for this purpose. Two series based on the studies of safety features of virtual reality technologies were carried out. In the first series, 20 healthy young male subjects, and in the second series 10 such subjects underwent the psychological interviews in the virtual space using the virtual reality system for a relatively short duration. Several measures of the physiological, biochemical, neurological, and psychological fatigue are measured before, during, and after the interview session. However, there were no significant changes in the measured objective parameters of fatigue. The features of the user reconfigurable virtual reality world creation as shown in the present study are thought to be very useful. The VR technology is shown to be a potentially powerful tool for the improvement of modern medical care.

In this study we examined the proper pressure of air boots for a person in a sitting position. Air boots can improve calf congestion by pulsatile calf compression. Higher pressure may improve calf congestion more, though it might decrease arterial blood flow. A photo-electric plethysmometer was put on the second toe of a foot to measure the amplitude of the pulse which represent arterial blood flow. A sensor of a near infrared oxygen monitor was put on the calf just above an air boot. A near infrared oxygen monitor can detect tissue reduced hemoglobin which exists almost only in venous blood. So, the concentration of tissue reduced hemoglobin could represent tissue venous blood concentration.When the air boots pressure was more than 140mmHg, the amplitude of the arterial pulse decreased to half of that without massage. Pressure less than 70mmHg didn't affect arterial blood flow. Meanwhile pressures of more than 70mmHg didn't show any difference in the improvement of calf congestion. So, we concluded that the proper pressure for air boots massage for calf congestion in a sitting position is less than 70mmHg.

Two different visual patterns presented separately to each eye can't fuse images. Only one of two patterns can be perceived exclusively and alternatively. This phenomenon is known as Binocular rivalry (BR.). We have been measuring BR. to investigate human visual information processing. Authers have already reported that the alteration of BR. dominance is not-symmetrical. (BR. asymmetry) Present study reports neither visual acuity nor eye dominance is not the origin of BR. asymmetry. Some aspects about the mechanism of BR. is discussed.

In order to analyze mechanisms of involuntary movement, readiness potentials of saliva swallowing were recorded in control and light sleep condition from healthy subjects. As a trigger signal for data averaging, surface EMG recorded from neck was used. Negative component of readiness potential before onset of swallowing was not observed clearly in sleep and control conditions. Sensory evoked potentials after swallowing were observed in both conditions. Result shows that it is possible to measure readiness potentials even in sleeping subjects.

In order to analyze the autonomic functioning during sleep, all night polygraphic measurement including the pulse transit time (PTT) was carried out with healthy subjects under sleep deprived and natural sleep condition. Sleep stages were classified based on the EEG recordings. Average and standard deviation of the PTT were calculated in each segment. Effect of sleep deprivation on the autonomic function was investigated.

Artificially evoked somatosensory illusion was investigated. Using synchronized stimulation to the Phantom arm, duration of the illusion and positioning error were measured. Emotional effects of the cutter knife on illusionary sensation were discussed.

Relationships between MTS and sleep stage distribution were investigated. Polygraphic measurements were carried out with healthy subjects under sleep deprived and control condition. Results showed that relative frequency of sleep stage 2 and stage REM before the MTS period changed under sleep deprived condition compare with control condition.

To investigate characteristics of circadian rhythm, all day holterrecording were analyzed. Power spectra were estimated from R-R interval series via FFT. High and low frequency components of R-R fluctuation were observed. We discussed the circadian profiles of R-R spectra and its sleep-related changes.

We study the characteristics of the Event-related variation of the blood flow, an experiment was carried out utilizing a strong emotional stimulation. Blood flow in the dermal tissue of the palm was analysed under the emotional condition. The premotor state in peripheral circulatory system was investigated.

Time series of the center of gravity were analysed to investigate the effect of visual distraction on posture control function. Visual distraction was created by rotating disk filled with geographical patterns. Specific fluctuation related to visual signal was observed. The role of visual sensory processing in posture control was discussed.

In order to analyze the sleep cycle in human natural sleep, physiological parameters were recorded from healthy adult subjects. Utilizing the spectral analysis of heart rate, autonomic state during sleep was investigated. Specific changes of LF and HF component of the spectra were observed in each sleep stage.