Elucidating Diurnal Patterns in Touch Desire Using Social Media Data Toward Design of Haptic Applications and Displays.

Advances in haptic technology have led researchers and engineers to seek out killer applications in which users can enjoy an experience of touch in AR/VR spaces. Such applications will respond appropriately to human desire for haptic experiences (i.e., touch desire) and thus it is essential for researchers and engineers to understand the nature of people's touch desires as they arise in the course of daily life. In this study, we employed Twitter data analysis to investigate a diurnal pattern in touch desire. Our results showed that touch desire identified in and extracted from Twitter texts did reveal a diurnal pattern. Touch desire tended to be at its lowest in the morning and increased as the day progressed. The time at which it peaked varied with the specific target of touch desire. Touch desire in relation to other people and objects reached its peak at night, but touch desire in relation to animals reached its peak at noon. These results were confirmed not only by our Twitter text analysis but also by data from other social media and an online survey. In addition, we found that the diurnal pattern of touch desire for each target shows a strong correlation with that of visual desire for the same target. This suggests that the diurnal pattern of touch desire is not limited to the sense of touch but is common to other sensory desires for each target. Our findings suggest that researchers need to take the time of day into account when investigating touch desire. Our findings also offer valuable insights for developers into the design of haptic applications and displays that takes into account the timing of daily peaks in touch desire.

Relationship Between Left-Right Dominancy of Prefrontal Cortex Activity and Heart Rate During Rest and Task Periods: An fNIRS Study.

BackgroundFunctional near-infrared spectroscopy (fNIRS) studies demonstrated that regulation of stress response of the autonomic nervous system is mediated by the left-right asymmetry of prefrontal cortex (PFC) activity. However, it is not yet clear whether PFC regulation of stress response is functioning only when the subject was under stress or even at rest without stress. In addition, the temporal responsivity of PFC regulation of stress response is not known.AimThis study aims to investigate the relationship between the left-right asymmetry of PFC activity and heart rate during both resting state and stressful state while performing a working memory task.ApproachTwenty-nine subjects were recruited to rest and conduct 2-back task, during which fNIRS and ECG were measured simultaneously.ResultsWe found weak correlation (r = 0.28, p = 0.137) between laterality index (LI) and heart rate in the task session, but no correlation in rest sessions at a group level. Moreover, weak but significant correlation was found only in the task session for all analysis intervals ranged from 2 s to 1 min.ConclusionIt is suggested that regulation of stress responses was mediated by the left-right asymmetry of PFC activity only when the subject was under stress stimuli and embody stress response did not affect PFC in reverse. This regulation can be observed at an analysis interval of no less than 2 s.

Toward Designing Haptic Displays for Desired Touch Targets: A Study of User Expectation for Haptic Properties via Crowdsourcing.

Things that people desire to touch in daily life are known to be limited to a number of specific targets (e.g., cats). The utilization of haptic displays to provide the experience of touching such desired targets is expected to enhance people's quality of life. However, it is currently unclear which haptic properties (e.g., hardness and weight) of desired targets should be rendered with haptic displays, and how they should be rendered. To address these issues, we conducted an experiment with 600 Japanese participants via crowdsourcing. Among the 600 participants, we identified potential users of haptic displays and analyzed their responses for each target. For each desired target, we identified the haptic properties in relation to which a "need for consistency" was felt by potential users between their expectations and actual impressions during touching. We also identified the haptic properties in relation to which a "biased impression" was held by potential users for each target. For example, potential users responded that cats were soft and that the actual impression of softness during touching needed to be consistent with their impression. Our results provide insights into the design of haptic displays for realizing desired touch experiences.

Age and Gender Differences in the Pseudo-Haptic Effect on Computer Mouse Operation in a Desktop Environment.

Pseudo-haptics is a method that can provide a haptic sensation without requiring a physical haptic device. The effect of pseudo-haptics is known to depend on the individual, but it is unclear which factors cause individual differences. As the first study establishing a calibration method for these differences in future research, we examined the differences in the pseudo-haptic effect on mouse cursor operation in a desktop environment depending on the age and gender of the user. We conducted an online experiment and collected data from more than 400 participants. The participants performed a task of lifting a virtual object with a mouse pointer. We found that the effect of pseudo-haptics was greater in younger or male participants than in older or female participants. We also found that the effect of pseudo-haptics, which varied with age and gender, can be explained by habituation to the mouse in daily life and the accuracy of detecting the pointer position using vision or proprioception. Specifically, the pseudo-haptic effect was higher for those who used the mouse more frequently and had higher accuracy in identifying the pointer position using proprioception or vision. The results of the present study not only indicate the factors that cause age and gender differences but also provide hints for calibrating these differences.

Tracking changes in touch desire and touch avoidance before and after the COVID-19 outbreak.

Touch is essential for survival, social bonding, and overall health. However, the COVID-19 pandemic calls for an abrupt withdrawal from physical contact, and the prolonged lockdown has left many people in solitude without touch for months. This unprecedented dissociation from touch has cast a shadow on people's mental and physical well-being. Here we approached the issue by examining COVID-19's impact on people's touch attitudes. We analyzed people's desire and avoidance for animate and inanimate targets based on large-scale Japanese Twitter posts over an 8-year span. We analyzed the impact of the COVID-19 outbreak with the difference-in-differences estimation method, which can estimate the impact while accounting for other changes over time such as seasonality or long-term effects. As a result, we found that people's desire for touching the human body and pet animals increased significantly after the COVID-19 outbreak and remained high afterward. In contrast, the avoidance of touching everyday objects (e.g., doorknobs and money) increased immediately after the outbreak but gradually returned to the pre-COVID-19 levels. Our findings manifest the impact of COVID-19 on human touch behavior. Most importantly, they highlight the sign of "skin hunger," a public health crisis due to social distancing, and call attention to the trend that people are becoming less aware of infection control as COVID-19 persists.

Multiplexed lighting system using time-division multiplexing.

Improvements in lighting and other indoor environmental conditions have gained considerable attention in different areas, including health and economics. Controlling the lighting environment is essential because, among the indoor factors, visual stimulation affects numerous human characteristics. Further, visual stimulation, including peripheral vision, affects people differently. Therefore, to improve the indoor environment with multiple occupants, each occupant must have an independent lighting environment. However, this cannot be achieved through conventional approaches. In this study, we propose a multiplexed lighting environment that can simultaneously realize multiple mutually independent lighting environments within a single space. We developed the proposed system using time-division multiplexing and conducted an experiment to clarify the influence of light multiplexing on human behavior and impression of the indoor environment. The experimental results showed that the proposed method changed the lighting operations of the users and improved their impression of the lighting environment. Furthermore, the proposed method provides a desirable lighting environment for all people within a single space, even when people in the same space desire different lighting environments.

Getting Insights From Twitter: What People Want to Touch in Daily Life.

Understanding what people want to touch in daily life has been one of the central topics in the fields of haptic science, engineering, and marketing. Several studies have addressed the topic, however, their findings were highly dependent on the experimental stimuli in the laboratory environment. In this study, we tried to gain insights into targets that people want to touch in daily life by conducting a Twitter survey. We collected a considerable amount of Japanese Twitter posts containing references to the desire for touch. To capture the motivation underlying these desires in relation to haptic properties, we used several queries that comprehensively covered exploratory procedures. The results showed that targets that people wanted to touch depended on the exploratory procedures in the queries used (e.g., "want to stroke" tended to target people and animals). We also found that these targets were desirable to touch not only for their haptic properties but also as a means of communicating with other people or living animals. Our findings would be important for understanding human haptic function in the real world and for developing consumer haptic displays and applications.

Survey of Pseudo-Haptics: Haptic Feedback Design and Application Proposals.

In the last two decades, the design of pseudo-haptics as a haptic presentation method that does not require a mechanical feedback device has been proposed in various research papers. Moreover, applications using pseudo-haptics have been proposed and evaluated in various contexts. However, the findings from these studies have not yet been comprehensively organized in a survey paper in the recent times. In this article, findings from a series of individual prior studies were summarized from the design through to the application proposals. First, we summarize visual stimuli designs based on the target haptic object properties to induce pseudo-haptics. Second, we summarize two special issues when designing pseudo-haptics; (1) workaround design for the visualized mismatch of visual stimuli and user input; and (2) the combination design of pseudo-haptics and physical stimuli. Third, application proposals that use pseudo-haptics for training, assistance, and entertainment are presented. This survey paper would help not only researchers in academia but also application developers who intend to use pseudo-haptics as a haptic presentation method.

Edge Vibration Improves Ability to Discriminate Roughness Difference of Adjoining Areas.

Researchers have studied the discrimination thresholds between different vibrotactile signals under various conditions. Humans cannot recognize slight differences in vibrotactile stimuli that are smaller than the perception threshold. This is a constraint in the vibrotactile design used in practical applications. This article focuses on the vibrational feedback at the "edge" between multiple areas, while previous studies have not considered this. We assume that the edge vibration not only emphasizes the presence of the edge itself, but also has an effect on the vibrotactile perception of the adjoining areas. Specifically, we hypothesize that the edge vibration would modify the user's ability to discriminate vibrotactile differences between adjoining areas. We conducted a user study to test this hypothesis. As a result, we found that presenting edge vibrations at the boundaries between adjacent textures makes it easier to discriminate the frequency and amplitude differences of the vibrations of those uneven textures. This article could increase the flexibility of vibrotactile design, and vibrotactile designers could use these results to design a wider variety of vibrations for adjacent areas.

IMP dehydrogenase-2 drives aberrant nucleolar activity and promotes tumorigenesis in glioblastoma.

In many cancers, high proliferation rates correlate with elevation of rRNA and tRNA levels, and nucleolar hypertrophy. However, the underlying mechanisms linking increased nucleolar transcription and tumorigenesis are only minimally understood. Here we show that IMP dehydrogenase-2 (IMPDH2), the rate-limiting enzyme for de novo guanine nucleotide biosynthesis, is overexpressed in the highly lethal brain cancer glioblastoma. This leads to increased rRNA and tRNA synthesis, stabilization of the nucleolar GTP-binding protein nucleostemin, and enlarged, malformed nucleoli. Pharmacological or genetic inactivation of IMPDH2 in glioblastoma reverses these effects and inhibits cell proliferation, whereas untransformed glia cells are unaffected by similar IMPDH2 perturbations. Impairment of IMPDH2 activity triggers nucleolar stress and growth arrest of glioblastoma cells even in the absence of functional p53. Our results reveal that upregulation of IMPDH2 is a prerequisite for the occurance of aberrant nucleolar function and increased anabolic processes in glioblastoma, which constitutes a primary event in gliomagenesis.

Modulating Fine Roughness Perception of Vibrotactile Textured Surface using Pseudo-haptic Effect.

Playing back vibrotactile signals through actuators is commonly used to simulate tactile feelings of virtual textured surfaces. However, there is often a small mismatch between the simulated tactile feelings and intended tactile feelings by tactile designers. Thus, a method of modulating the vibrotactile perception is required. We focus on fine roughness perception and we propose a method using a pseudo-haptic effect to modulate fine roughness perception of vibrotactile texture. Specifically, we visually modify the pointer's position on the screen slightly, which indicates the touch position on textured surfaces. We hypothesized that if users receive vibrational feedback watching the pointer visually oscillating back/forth and left/right, users would believe the vibrotactile surfaces more uneven. We also hypothesized that as the size of visual oscillation is getting larger, the amount of modification of roughness perception of vibrotactile surfaces would be larger. We conducted user studies to test the hypotheses. Results of first user study suggested that users felt vibrotactile texture with our method rougher than they did without our method at a high probability. Results of second user study suggested that users felt different roughness for vibrational texture in response to the size of visual oscillation. These results confirmed our hypotheses and they suggested that our method was effective. Also, the same effect could potentially be applied to the visual movement of virtual hands or fingertips when users are interacting with virtual surfaces using their hands.