Digital Human Representations for Health Behavior Change: A Structured Literature Review

Organizations have increasingly begun using digital human representations (DHRs), such as avatars and embodied agents, to deliver health behavior change interventions (BCIs) that target modifiable risk factors in the smoking, nutrition, alcohol overconsumption, and physical inactivity (SNAP) domain. We conducted a structured literature review of 60 papers from the computing, health, and psychology literatures to investigate how DHRs’ social design affects whether BCIs succeed. Specifically, we analyzed how differences in social cues that DHRs use affect user psychology and how this can support or hinder different intervention functions. Building on established frameworks from the human-computer interaction and BCI literatures, we structure extant knowledge that can guide efforts to design future DHR-delivered BCIs. We conclude that we need more field studies to better understand the temporal dynamics and the mid-term and long-term effects of DHR social design on user perception and intervention outcomes

DESIGNING BETTER EXERGAMES: APPLICATION OF FLOW CONCEPTS AND THE FITT PRINCIPLE TO FULL BODY EXERTION VIDEO GAMES AND FLEXIBLE CHALLENGE SYSTEMS

Exercise video games have a recognized potential for widespread use as tools for effective exercise. Current exergames do not consistently strike a successful balance between the “fun gameplay” and “effective exercise” aspects of the ideal exergame. Our research into the design of better exergames applies existing gameflow research and established exercise guidelines, such as those published by the American College of Sports Medicine, to a collection of four custom exergames: Astrojumper, Washboard, Sweet Harvest and Legerdemain implement full-body motion mechanics that support different types of exercise, and vary in intended duration of play, game complexity, and level of physical challenge. Each game also implements a difficulty adjustment system that detects player performance from in-game data and dynamically adjusts game difficulty, in order to balance between a player’s fitness level and the physical challenge presented by the game. We have evaluated the games produced by our design approach through a series of user studies on players’ physiological and psychological responses to gameplay, finding that balance between challenge types (cognitive or physical) is an important consideration along with challenge-skill balance, and further, that game mechanics able to support creativity of movement are an effective means of bridging between gameplay and exercise in order to improve the player experience

Exploring movement and enjoyment in VR games

Physical activity and health is declining globally as more and more people adopt increasingly sedentary lifestyles. This decline comes with many health-related risks in people of all ages and demographics. Video games are often seen as a large cause of this, which is why many game developers and companies have attempted to combat this stigma by creating games and systems that provide means of exercise while gaming. These types of games are commonly known as exergames, and Virtual Reality is the newest technology that is attempting to make use of exergaming with immersive and engaging games. Performing physical activity that has a high potential to be effective, engaging, and enjoyable for users, from the comfort of their own homes, is a proposition that VR gaming has the potential to fulfill for many. For this purpose, this research seeks to explore the possibilities of enjoyable physical activity in VR exergames and find answers for which design themes are especially effective for enjoyable movement and long-term engagement. The research was done with a basis on phenomenology and phenomenography, which are both studies heavily based on experiences of specific phenomena. Five different VR games were chosen for testing for the study and analyzed based on the provided movement and activity, as well as enjoyment. This data was measured and gathered via heart rate tracking, and a focus on the experiences of flow in VR. Additionally, an open written interview was performed with a participant with years of previous experience in VR gaming to gather more data for an outside experience view. The results of these experiences and feedback were then analyzed and compared to previous research on the subjects of VR enjoyment and exercise. The conclusions gathered from the research were formed into a list detailing beneficial design themes that help improve enjoyability and engaging movement in VR exergames. The provided list can serve as a helpful tool to both developers and future research on the matter of enjoyability and engaging movement in VR games, from a user experience perspective. Furthermore, Virtual Reality games can be said to positively increase engagement and enjoyability for physical activity when designed well. Future research can expand on this study by widening the scope of participants and including a larger variety of VR games to gather more data on user experiences.Fyysinen liikkuvuus ja hyvinvointi on laskusuunnassa maailmanlaajuisesti, sillä yhä useampi henkilö adoptoi elämäntyylejä, joissa liikkuvuus on vähäistä. Tämä tuo mukanaa monia hyvin-vointiin liittyviä riskejä kaikille ikäluokille. Videopelit nimetään usein yhdeksi isoksi syyksi yleiseen liikkuvuuden vähentymiseen maailmalla. Pelintekijät ja pelifirmat ovat pyrkineet taistelemaan tätä vastaan kehittämällä systeemejä ja pelejä, jotka yhdistävät pelaamisen ja liikku-misen. Tämän tyylisiä pelejä kutsutaan yleisesti nimellä exergames, joka tulee englanninkielen sanoista exercise, eli liikunta, ja game, eli peli. Virtuaalinen todellisuus (VR) on uusin teknologia, joka pyrkii hyödyntämään liikkuvuutta peleissä. Idea kotona suoritettavasta tehokkaasta ja nautinnollisesta fyysisestä liikkunnasta, joka viehättää käyttäjän mukaansa on ehdotus, jonka VR pelaaminen mahdollistaa monelle. Tämä tutkinto pyrkii tätä tarkoitusta varten tutkimaan liikkuvuutta ja nautintoa VR-peleissä, ja löytämään pelimekaniikkoja ja teemoja, jotka mahdollistavat suuremman nautinnon ja tehokkaamman liikkumisen näissä peleissä. Tämän tutkimuksen menetelmänä toimii yhdistelmä fenomenologiaa ja fenomenografiaa, jotka ovat laajalti omiin ja muiden suoriin kokemuksiin perustuvia laadullisia menetelmiä. Tutkimukseen on otettu testattavaksi viisi eri VR-peliä, joita tulen itse pelaamaan ja keräämään tietoa ja kokemuksia niiden nautinnollisuudesta ja liikkuvuudesta. Liikkuvuudesta kerätään tieto sykemittarin avulla, ja nautinnollisuuden kokemuksien perustana toimii laajalti tut-kittu flow-malli, joka mittaa erilaisia tuntemuksia aktiviteeteissä. Tämän lisäksi tutkimuksessa suoritetaan kirjallinen haastattelu ulkopuolisen henkilön kanssa, jolla on vuosien kokemuksia VR-peleistä. Näistä tutkimuksista löydetyt tiedot kerätään ja analysoidaan, sekä verrataan aiempiin tutkimuksiin ja löydöksiin VR liikunnan alalla. Tutkimuksen löydöksistä luotiin lista, jossa luetellaan hyödyllisiä teemoja liikkuvuuden ja nau-tinnollisuuden suhteen VR-peleissä. Pelintekijät ja tutkijat voivat hyödyntää tätä listaa vertausarvollisesti pelinkehityksessä ja muissa VR liikuntaan liittyvissä tutkimuksissa. Nämä teemat antavat erityisesti käyttäjäkokemuksellisesti hyödyllistä tietoa VR-pelien liikkuvuudesta ja nautinnollisuudesta. Tämän lisäksi tässä tutkimuksessa voidaan vahvistaa löydöksiä VR liikunnan yleisestä hyödyllisyydestä nautinnollisen ja houkuttelevan liikunnan edistämisessä. Jatkotutkimuksissa voidaan testata useampia VR-pelejä sekä laajentaa osallistujamäärää ja kerätä laajemmin käyttäjäkokemuksia

Manipulating Self-Avatar Body Dimensions in Virtual Worlds to Complement an Internet-Delivered Intervention to Increase Physical Activity in Overweight Women

[EN] Virtual reality has been found to be a useful tool for positively influencing relevant psychological variables in order to increase physical activity (PA), especially in the overweight population. This study investigates the use of avatars and their physical variations to extend the effectiveness of existing interventions to promote PA. The main objective is to analyze the influence of the avatars' body dimensions on the efficacy of an Internet intervention to increase PA levels and improve other relevant variables (motivation toward PA, enjoyment, anxiety, self-efficacy, and PA goals). A total of 42 overweight women received a brief online intervention, and they were randomly assigned to one of three conditions: the "Ideal avatar" (IAC: participants are represented by avatars with ideal body dimensions); the "Real avatar" (RAC: participants are represented by avatars with participants' current body dimensions); and the "Non avatar" (NAC: participants are not represented by avatars). Results showed that the online intervention was effective in increasing PA practice and self-efficacy expectations. However, manipulating the body dimensions of avatars did not improve this intervention, although ideal avatars helped to reduce the anxiety experienced during PA in this population.This study was funded by "INTERSABIAS" project (PROMETEO/2018/110, Conselleria d'Educacion, Investigacio, Cultura i Esport de la Generalitat Valenciana) and by CIBER of Physiopathology of Obesity Nutrition, an initiative of ISCII (ISCII CB0603/0052).Navarro, J.; Cebolla, A.; Llorens Rodríguez, R.; Borrego, A.; Baños, RM. (2020). Manipulating Self-Avatar Body Dimensions in Virtual Worlds to Complement an Internet-Delivered Intervention to Increase Physical Activity in Overweight Women. International Journal of Environmental research and Public Health (Online). 17(11):1-14. https://doi.org/10.3390/ijerph17114045S1141711Ding, D., Lawson, K. D., Kolbe-Alexander, T. L., Finkelstein, E. A., Katzmarzyk, P. T., van Mechelen, W., & Pratt, M. (2016). 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On the Persuasive Power of Videogame avatars on Health-related behaviours

Background: Avatars are representations of the self in a virtual environment. They have been used to influence behaviour and may represent a promising avenue for designing interventions to promote health-related behaviour change. Aim: To determine the extent to which a representation of the self in a videogame influences health-related behaviours. Method: In addressing the aim of the thesis, a mixed methods approach was adopted. This started with a systematic review investigating the effectiveness of various attempts at health persuasion using avatar appearance manipulation. Next, a qualitative study investigating gamers’ avatar design preferences and experiences of playing an exergame with an idealised, self-similar avatar was conducted. The quantitative phase of the thesis involved three quantitative studies investigating the existence, ambivalence, and variance of stereotypes associated with plus-sized and athletic physiques over three modalities (text, image, video); and a replication-extension of an exergame-based Proteus Effect study involving larger-bodied and ‘average’ avatars. In this latter study, a bespoke exergame was developed that used the stimuli developed in the previous studies as avatars. Results: The systematic review (Chapter 4) revealed that a small number of studies had investigated using avatars to promote health related behaviour, and a common finding was that using larger-bodied (compared with athletic) avatars in exergames resulted in reduced physical-activity. Since this was explained in terms of stereotypical behaviours, such as laziness, being assimilated into the players’ behaviour, the qualitative study (Chapter 5) explored participants’ accounts of being restricted to an athletic avatar and found that this was not always a positive experience. To explore this further, Chapter 6 investigated the stereotype structures of plus-sized and athletic bodies were both found to suggest ambivalence. Text descriptions of prototypical ‘athletic’ groups (Chapter 6), and images of virtual humans with athletic bodies (Chapter 7) were rated as more competent, more arrogant, and less friendly compared with larger-bodied examples. Negative stereotypes, such as laziness, were reflected in evaluations of larger bodied representations, but so was the potentially positive trait of affability. In Chapter 8, larger-bodied exemplars that were animated with counter-stereotypical information (running on the spot) were rated less negatively than those that were stationary. When the exemplars were used as avatars, there was no evidence for behaviour change as a function of avatar-physique in the experimental replication study (Chapter 9). Conclusion: By using methods derived from existing social psychological theories, it is possible to create representations of larger bodies that are evaluated more positively. Further, there may be negative consequences to relying on athletic-bodied avatars to encourage exercise. Although there was no strong evidence that participants behaviour was affected by the type of avatar used, an argument can be made for allowing users to explore a broader range of physiques and presenting larger-bodied characters positively as competent agents

An investigation into the efficacy of avatar-based systems for student advice

Student support is an important function in all universities. Most students expect access to support 24/7, but support staff cannot be available at all times of day. This paper addresses this problem, describing the development of an avatar-based system to guide students through the materials provided by a university student employability service. Firstly, students and staff were surveyed to establish the demand for such a system. The system was then constructed. Finally, the system was evaluated by students and staff, which led to a clearer understanding of the optimal role for avatar-based systems and consequent improvements to the system’s functionality

An investigation into the efficacy of avatar-based systems for student advice

Student support is an important function in all universities. Most students expect access to support 24/7, but support staff cannot be available at all times of day. This paper addresses this problem, describing the development of an avatar-based system to guide students through the materials provided by a university student employability service. Firstly, students and staff were surveyed to establish the demand for such a system. The system was then constructed. Finally, the system was evaluated by students and staff, which led to a clearer understanding of the optimal role for avatar-based systems and consequent improvements to the system’s functionality

Development of Immersive and Interactive Virtual Reality Environment for Two-Player Table Tennis

Although the history of Virtual Reality (VR) is only about half a century old, all kinds of technologies in the VR field are developing rapidly. VR is a computer generated simulation that replaces or augments the real world by various media. In a VR environment, participants have a perception of “presence”, which can be described by the sense of immersion and intuitive interaction. One of the major VR applications is in the field of sports, in which a life-like sports environment is simulated, and the body actions of players can be tracked and represented by using VR tracking and visualisation technology. In the entertainment field, exergaming that merges video game with physical exercise activities by employing tracking or even 3D display technology can be considered as a small scale VR. For the research presented in this thesis, a novel realistic real-time table tennis game combining immersive, interactive and competitive features is developed. The implemented system integrates the InterSense tracking system, SwissRanger 3D camera and a three-wall rear projection stereoscopic screen. The Intersense tracking system is based on ultrasonic and inertia sensing techniques which provide fast and accurate 6-DOF (i.e. six degrees of freedom) tracking information of four trackers. Two trackers are placed on the two players’ heads to provide the players’ viewing positions. The other two trackers are held by players as the racquets. The SwissRanger 3D camera is mounted on top of the screen to capture the player’