We have synthesized new Tsai-type Yb-based intermediate-valence approximant crystals (ACs) with different degree of approximation to quasicrystal, Zn--Au--Yb 1/1 and 2/1 AC, and studied the external pressure effect on their Yb mean-valence $\nu$. Whereas 1/1 AC distinctly exhibits a first-order-like jump in $\nu$ at a transition pressure $P_{\rm v}$, 2/1 AC only shows an indistinct anomaly at $P_{\rm v}$. We have also studied the pressure dependence of the $\nu$ of Au--Al--Yb 1/1 AC, which is a prototypal AC exhibiting pressure-induced quantum criticality. It shows a continuous valence anomaly at a critical pressure $P_{\rm c}$ where the magnetic susceptibility diverges toward zero temperature, in contrast to the valence jump in the Zn--Au--Yb 1/1 AC. These results are discussed based on a theoretical model of quantum critical valence fluctuation.

In this paper, we discuss the effect of using an avatar on interpersonal communication. Past research has confirmed that changes in communication and cognition such as the “Proteus effect” and “disappearance of stereotypes” occur. In this research, we are discussing whether we can improve our own wellbeing. Users with a tendency to stutter cannot speak well face-to-face, but wearing an avatar reduces the number of times they stutter, and it was confirmed that stress was reduced from the biological response. Based on this, we discuss the impact of avatars on communication-related wellbeing.

With the rapid development of the international community, foreign language learning has become increasingly important. Listening training is a particularly important component of foreign language learning. The most difficult aspect of listening training is the development of speech discrimination ability, which is crucial to speech perception. General behavioral training requires a substantial amount of time and attention. To address this, we previously developed a neurofeedback (NF) training system that enables unconscious learning of auditory discrimination. However, to our knowledge, no studies have compared NF training and general behavioral training. In the present study, we compared the learning effects of NF training, general behavioral training, and a combination of both strategies. Specifically, we developed a gamified and adapted NF training of auditory discrimination. We found that both NF training and general behavioral training enhanced behavioral performance, whereas only NF training elicited significant changes in brain activity. Furthermore, the participants that used both training methods exhibited the largest improvement in behavioral performance. This indicates that the combined use of NF and general behavioral training methods may be optimal for enhancing auditory discrimination ability when learning foreign languages.

From the maneuvering training research of the surgical support robot DaVinci, it is reported that the reduction of the geometric inertial constraint that can be the motion resistance does not necessarily lead to the improvement of the learning speed. In other words, it is considered that the trainee is proficient in the force field due to restraint as a clue. Therefore, this report verifies that proper restraint promotes skill proficiency.

A significant problem in brain–computer interface (BCI) research is decoding — obtaining required information from very weak noisy electroencephalograph signals and extracting considerable information from limited data. Traditional intention decoding methods, which obtain information from induced or spontaneous brain activity, have shortcomings in terms of performance, computational expense and usage burden. Here, a new methodology called prediction error decoding was used for motor imagery (MI) detection and compared with direct intention decoding. Galvanic vestibular stimulation (GVS) was used to induce subliminal sensory feedback between the forehead and mastoids without any burden. Prediction errors were generated between the GVS-induced sensory feedback and the MI direction. The corresponding prediction error decoding of the front/back MI task was validated. A test decoding accuracy of 77.83–78.86% (median) was achieved during GVS for every 100[Formula: see text]ms interval. A nonzero weight parameter-based channel screening (WPS) method was proposed to select channels individually and commonly during GVS. When the WPS common-selected mode was compared with the WPS individual-selected mode and a classical channel selection method based on correlation coefficients (CCS), a satisfactory decoding performance of the selected channels was observed. The results indicated the positive impact of measuring common specific channels of the BCI.

Percutaneous electrical stimulation modifies brain and nerve excitability and also stimulates various sensory organs. Although it can be applied to sensory information displays, virtual reality, and human augmentation, the effect on human intranasal chemosensation, including olfaction, is not clearly understood. In this paper, we introduce galvanic olfactory stimulation, in which non-invasive electrical stimulation induces virtual intranasal chemosensation. For this purpose, we designed an electrode configuration using a finite element analysis simulation. We then conducted two psychophysical experiments comparing different stimulation configurations and asking subjects to describe their sensation experiences. The results demonstrate that galvanic olfactory stimulation using a pair of electrodes at the nasal bridge and the dorsal surface of the neck induces virtual irritating intranasal chemosensation. This observation suggests that, at the very least, the proposed galvanic olfactory stimulation method induces irritating intranasal chemosensation. This implies that an electric current stimulates the trigeminal nerve in the inner region of the nasal cavity. To the best of our knowledge, this is the first report to demonstrate virtual intranasal chemosensation using non-invasive electrical stimulation of the external surface of the nose.

Listening is critical for foreign language learning. Listening difficulties can occur because of an inability to perceive or recognize sounds while listening to speech, whereas successful listening can boost understanding and improve speaking when learning a foreign language. Previous studies in our laboratory revealed that EEG-neurofeedback (NF) using mismatch negativity event-related brain potential successfully induced unconscious learning in terms of auditory discrimination of speech sounds. Here, we conducted a feasibility study with a small participant group (NF group and control group; six participants each) to examine the practical effects of mismatch negativity NF for improving the perception of speech sounds in a foreign language. Native Japanese speakers completed a task in which they learned to perceive and recognize spoken English words containing the consonants “l” or “r”. Participants received neurofeedback training while not explicitly attending to auditory stimuli. The results revealed that NF training significantly improved the proportion of correct in discrimination and recognition trials, even though the training time for each word pair was reduced to 20% of the training time reported in our previous study. The learning effect was not affected by training with three pairs of words with different vowels. The current results indicate that NF resulted in long-term learning that persisted for at least 2 months.

Galvanic taste stimulation (GTS) is a non-invasive electrical stimulation of sensory nerves that induces, inhibits, and enhances taste sensation. It has been shown that the cathodal GTS taste enhancement effect occurs when only cathodal electrodes are attached in or near the mouth, while anodal GTS, whose anodal electrodes are attached in or near the mouth, induces an electrical taste sensation rather than taste enhancement. In the present study, we focused on the taste enhancement effect of anodal GTS, enhancing the salty taste produced by a sodium chloride (NaCl) aqueous solution during stimulation. In this study, GTS was applied to the chin rather than the inner mouth so as not to disturb natural eating and drinking behavior, according to a previous study. To demonstrate and quantitatively evaluate its enhancement effect, we conducted two psychophysical experiments in which subjects were asked to indicate the intensity of the saltiness perceived during electrical stimulation by adjusting the concentration of aqueous NaCl to achieve a solution of equivalent saltiness. We discovered that the perceived intensity increased as the current intensity applied to the chin increased. Moreover, the magnification ratios against the baseline exceeded 1 under all conditions of the NaCl aqueous solution. These results indicate that anodal GTS is effective in enhancing the salty taste of NaCl aqueous solutions.

The human body schema has innate characteristics, it is known to change through the process of growth and injury, thus making it mutable. And there have been many attempts to augment or enhance limbs as perceptual abilities and effectors in body function augmentation technology. However, the methodology that allows for a stronger sense of ownership for augmented body parts was unclear. Therefore, we considered that, in the rubber hand illusion (RHI) paradigm, neurofeedback could enhance the sense of ownership in the process of adapting to the consistency or inconsistency between visual and tactile stimuli. And we focused our attention on neurofeedback learning by mismatch negativity (MMN). MMN-based learning has been shown to be effective for subconscious learning. In this paper, we consider RHI as conscious adaptive learning, and consider that it can be approached by MMN in the same way. However, in order to use MMNs for RHI, it is necessary to detect the respons as EEG measurements for multimodal inconsistency as the secondary clue rather than the inconsistency of sensory stimulus prediction as primary clue. In this paper, we evaluate the MMN for the visual-tactile stimuli of the extra body in which the sense of ownership occurs in the RHI paradigm. It detects MMNs that are only caused by discrepancies between the senses. And we detect MMN that are only caused by inconsistency between multimodal.

Neurofeedback is a sub-category of biofeedback that is concerned with using brain signals as the source of training data in a feedback loop. The neurofeedback training procedures in this study focused on the mismatch negativity (MMN) component, an event-related potential (ERP) that reflects the cognitive processes of auditory discrimination ability. This paper proposes a neurofeedback game that allows the subject to control the game with the help of auditory discrimination ability based MMN. We examined whether the proposed game is effective in helping native Japanese speakers discriminate speech sounds in English that are usually difficult to be differentiated. Subjects seemed to improve significantly in speech sound discrimination after playing a number of game sessions demonstrates the effectiveness of the proposed game in speech sounds learning in foreign language.

Biometrics has recently been the go-to authentication method in most electronic devices due to its convenience. There are two types of biometrics - static biometrics and dynamic biometrics. Hand gesture can both static and dynamic biometrics. Static hand gesture can be in the form of static hand sign; whereas dynamic hand gesture can be in the form of moving finger, hand, or arm. And due to its continuity, dynamic biometrics is usually correlated with behavioral. Hand gesture can also be a combination of both static and dynamic biometrics, for example continuous hand signs, where the hand sign is the static and the changes from one sign to another is the dynamic. In our research, we will be using the combination of both static and dynamic hand gesture. In order to simulate the worst case scenario, all the participants were asked to perform the same static hand gesture. From the result, it has been shown that the system can discern individuals through their gesture behavior. The accuracy rate from the confusion matrix and equal error rate from receiver operating characteristic (ROC) are above 0.84 and below 0.0701 respectively.

We propose a pseudo inner reading voices (IRVs) interface to perform decision making from an external perspective, thereby creating an illusion that information is being processed by oneself. This does not imply that decisions are made according to someone else's instructions; rather, this creates an illusion that the decision was willfully made by one's own self. The belief that a person made his/her own decision can help reduce the mental workload. Although unfamiliarity with recorded voices has often been studied in perceptual research, there exists no filter that can convert recorded voices into familiar voices. Therefore, we reconstructed bone and air conduction models, measured the bone- and air-conducted sounds separately, weighted the ratio of both sounds, and superimposed them to reproduce a subject's own voice. Next, in the counting experiment, it was confirmed that the pseudo IRVs can bias the information processing of human beings without increasing the mental workload.

-Existing studies have reported that the Full Body Ownership Illusion let users perceive a virtual body as our own body. It has also revealed the Proteus Effect that avatars' appearance could affect user's behavior, attitude and mental condition by inducing the Full Body Ownership Illusion. While many studies have focused on a humanoid avatar and its psychological effects, a previous study has reported that the Full Body Ownership Transfer can be induced even in the case of an animal avatar. In case of inducing the Full Body Ownership Transfer on an animal avatar, it can be expected to induce the psychological effect different from the one by a human avatar. Hence, this study examines a dragon avatar, which has impression of strong body and flight ability, can reduce the fear of height as the Proteus Effect by the Full Body Ownership Transfer. We carried out an experiment with some scenarios where a subject transformed into a dragon and flied into a height, comparing with operating a human avatar. The results showed that transforming into the dragon avatar can improve subjective score and physiological reaction for the fear of height.

The trochoid is a geometrically complete solution for realizing omnidirectional mobility with a rotating mechanism. The proposed mechanism is implemented as a novel omnidirectional vehicle with following a geometrically complete trochoidal trajectory. Because the mechanism has a large camber angle, it has an improved ability to travel past rough terrain as compared to a regular vehicle with regular wheels. In this paper, a complete mechanical control using link mechanism to generate not only the steering angle and camber angle for an ideal trochoidal wave but also the angular velocity of the wheel axis is proposed.

An experiment was carried out using a liquefied natural gas carrier model with two prismatic chamfered tanks. The coupled behavior of the ship motion and the liquid inside the tanks was studied, and the experimental data were compared with numerical results. The ship motion was calculated with the strip method, and the liquid motion was calculated with a finite difference method. The tanks used in the experiment have a length-to-breadth ratio near 1, and in addition to a two-dimensional liquid sloshing, a rotational motion of the liquid was also observed when the excitation was near the tank natural frequency. The effects of these different modes on the coupled motion are discussed.