Riccardo Sioni

Affective computing vs. affective placebo

Relaxation training is an application of affective computing with important implications for health and wellness. After detecting user?s affective state through physiological sensors, a relaxation training application can provide the user with explicit feedback about his/her detected affective state. This process (biofeedback) can enable an individual to learn over time how to change his/her physiological activity for the purposes of improving health and performance. In this paper, we provide three contributions to the field of affective computing for health and wellness. First, we propose a novel application for relaxation training that combines ideas from affective computing and games. The game detects user?s level of stress and uses it to influence the affective state and the behavior of a 3D virtual character as a form of embodied feedback. Second, we compare two algorithms for stress detection which follow two different approaches in the affective computing literature: a more practical and less costly approach that uses a single physiological sensor (skin conductance), and a potentially more accurate approach that uses four sensors (skin conductance, heart rate, muscle activity of corrugator supercilii and zygomaticus major). Third, as the central motivation of our research, we aim to improve the traditional methodology employed for comparisons in affective computing studies. To do so, we add to the study a placebo condition in which user?s stress level, unbeknown to him/her, is determined pseudo-randomly instead of taking into account his/her physiological sensor readings. The obtained results show that only the feedback presented by the single-sensor algorithm was perceived as significantly more accurate than the placebo. If the placebo condition was not included in the study, the effectiveness of the two algorithms would have instead appeared similar. This outcome highlights the importance of using more thorough methodologies in future affective computing studies. Relaxation training has important implications for health and wellness.We propose a novel biofeedback-controlled game for relaxation training.We compare two stress detection solutions for the game and a placebo condition.Only one of the two solutions produced better results than the placebo.We highlight methodological implications for the evaluation of affective computing systems.

Serious games for emergency preparedness

We propose a serious game that simulates a terror attack in a train station.Our study contrasts an interactive vs. non-interactive version of the simulation.We use Protection Motivation Theory as design guidance for the simulations.Both simulations improve knowledge, self-efficacy and severity perception.Interactivity of the simulation enhances risk perception and emotional response. Emergency preparedness is a relevant emerging application of serious games. A general issue in exploiting such approach concerns the breadth of the population that can be reached by serious games. Indeed, serious games need to be actively played and this can restrict their user population, because there are people who have no experience with video games or do not like them or do not have the proper hardware to play them. Moreover, there are organizational contexts in which a non-interactive presentation is preferred because it can be given in a more convenient and less costly way with simple traditional media, i.e., printed materials, slides or videos. This paper deals with the possibility of generating and using a non-interactive version of the experience provided by serious games. First, we propose a serious game that simulates a mass emergency caused by a terror attack in a train station. To obtain design guidance, we explore psychological models that explain how people are motivated to protect themselves from danger. Then, we generate the non-interactive version of the terror attack simulation and we contrast it with the interactive version. Results of our study show that both versions of the simulation can provide positive outcomes in learning, risk severity perception and self-efficacy, but they differ in how much they affect users threat appraisal and emotional response.

Stress Detection Using Physiological Sensors

Physiological signals such as electrodermal activity and heart rate can help computing systems detect a users stress level. Integrating additional measures not yet exploited by such systems could significantly increase stress-detection accuracy, enabling many new applications.

Psychological and physiological responses to stressful situations in immersive virtual reality

Several studies in the literature have shown positive psychophysical effects during or immediately after mindfulness meditation. However, the extent to which such positive effects are maintained in real-life, stressful contexts, remains unclear. This paper investigates the effects of an 8-week mindfulness-oriented meditation (MOM) program on the psychological and physiological responses evoked by immersive virtual environments (IVEs) that simulate emergency situations that may occur in life. Before and after the 8-week period, healthy MOM participants and a group of controls not involved in any meditation course were administered self-report measures of mindfulness and anxiety, and acted in the IVEs while a set of physiological parameters were recorded. Responses of MOM participants to the immersive virtual experiences were different from those of controls. MOM participants showed increased mindfulness and decreased anxiety levels. They also showed decreased heart rate and corrugator muscle activity while facing IVEs. We explain these results in terms of the awareness and acceptance components of mindfulness. More generally, the present experimental methods could also open up new lines of research that combine psychological and physiological indices with ecologically valid stimuli provided by IVEs in an effort to increase understanding of the impact of mindfulness meditation on realistic life situations. We exposed participants to stressful immersive virtual environments (IVEs).One group of users followed an 8-week mindfulness-oriented meditation course (MOM).The other group of users was a control group not involved in meditation.MOM participants showed higher mindfulness and lower anxiety than controls.MOM also led to decreases in heart rate and corrugator muscle activity in IVEs.

Mortality salience in virtual reality experiences and its effects on users attitudes towards risk

Virtual reality (VR) is increasingly used as a persuasive technology for attitude and behavior change. This paper considers Terror Management Theory (TMT), one of the notable theories that have not been considered so far in persuasive technology, and aims at exploring its use in VR experiences. First, we show that a VR experience can be used to effectively elicit mortality salience (MS), which makes TMT applicable. Then, we evaluate the effects of the VR experience on attitudes towards risk. Wearing a head-mounted display (HMD), participants explored one of two virtual environments (VEs). In a first group of participants, the VE represented a cemetery with MS cues like tombs and burial recesses. In a second group of participants, the MS cues were removed, and the VE looked like a public park. Results show that the MS cues manipulation changed the effects of the VR experience on users attitudes towards risk, as TMT would predict. Moreover, results revealed a relationship between MS elicited through VR and physiological correlates of arousal. Finally, we show that users personality traits can moderate the effects of the VR experience on attitudes towards risk. Virtual reality (VR) is increasingly used as a persuasive technology.This paper explores the use of Terror Management Theory (TMT) in VR experiences.We show that mortality salience (MS) can be elicited in VR, making TMT applicable.The MS manipulation had an effect on users attitudes towards risk and arousal.Personality traits of users can moderate the effects of the VR experience.

Exploring Eye-Blink Startle Response as a Physiological Measure for Affective Computing

In affective computing, detection of stress and negative emotions with physiological measures typically employs well-known signals such as skin conductance, activity of cheeks and forehead muscles, heart rate or heart rate variability. However, psychophysiology experiments in the literature offer additional measures (such as eye-blink startle response) not yet exploited in affective computing applications. Procedures to elicit eye-blink startle responses are often based on acoustic stimuli, in particular short bursts of intense white noise. Unfortunately, following this approach in affective computing applications would not be natural, because the artificial white noise bursts would be intrusive sounds unrelated to the user experience. They would thus distract the user from the meaningful events in the application and users (conscious or unconscious) attempts to relate those events to the artificial stimuli would be unsuccessful and frustrating, making the stimuli detrimental to the user experience. Our research aims at exploring if sounds that have a meaningful relation with the events in the application could be used as an alternative to white noise bursts. The study we present in this paper compares physiological responses of users of a 3D virtual environment in two conditions (measurement of eye-blink startle response to white noise or to an alternative sound that is related to the experience), showing that the two types of acoustic stimuli produce a similar intensity of startle response. This result suggests that eye-blink startle response could be used in natural ways to extend the set of physiological measures employed in affective computing.

Existential video games: Proposal and evaluation of an interactive reflection about death

Abstract Philosophers and psychologists as well as popular media (novels, theatrical plays, movies) often propose reflections about human mortality. This paper aims at exploring how new media like video games could be used to encourage users to reflect about death, and about the impact of death awareness on their lives. After defining existential video games (EXGs), we propose and evaluate Existence, an EXG that aims to expose users to different attitudes towards death, and to encourage them to reflect about death and their own mortality. We studied the experience elicited by Existence through a qualitative analysis of users’ interviews. Results show that Existence was able to elicit death reflection in participants. Furthermore, the game evoked both negative and positive emotions that, as explained by theories in social psychology, follow directly from mortality awareness and participants’ attempt to cope with fear of death.

Mobile Three-Dimensional Maps for Wayfinding in Large and Complex Buildings: Empirical Comparison of First-Person Versus Third-Person Perspective

The computational capabilities of todays smartphones make it possible to take advantage of mobile three-dimensional (3-D) maps to support navigation in the physical world. In particular, 3-D maps might be useful to facilitate indoor wayfinding in large and complex buildings, where the typical orientation cues (e.g., street names) and location tracking technologies that can be used outdoors are unavailable. The use of mobile 3-D maps for indoor wayfinding is still largely unexplored and research on how to best design such tools has been scarce to date. One overlooked but important design decision for 3-D maps concerns the perspective from which the map content should be displayed, with first-person and third-person perspectives being the two major options. This paper presents a user study involving wayfinding tasks in a large and complex building, comparing a mobile 3-D map with first-person perspective, a mobile 3-D map with third-person perspective, and a traditional mobile 2-D map. The first-person perspective shows the mobile 3-D map of the building from a floor-level egocentric point of view, whereas the third-person perspective shows the surroundings of the user from a fixed distance behind and above her position. Results of the study reveal that the mobile 3-D map with third-person perspective leads to shorter orientation time before walking, better clarity ratings, lower workload, mental demand and effort scores, and higher preference score compared to the mobile 3-D map with first-person perspective. Moreover, it leads to shorter orientation time before walking, better pleasantness ratings, lower mental demand scores, and higher preference score compared to the mobile 2-D map.