Taking a Walk on the Wild Side: Effects of Walking in Synchrony with Pitch-Altered Footstep Sounds on Body Perception in Outside the Lab ContextsThe 'Footsteps Illusion' shows that pitch-altering footstep sounds in real-time affects body perception, gait, and emotion: high versus low frequencies evoke a lighter versus heavier body. We tested whether this illusion extends beyond the lab, where environmental factors matter. Using a mixed-methods approach, twenty-eight participants used a minimal setup to synchronize with three prerecorded pitch-altered footstep soundtracks: Control, High-Frequency, and Low-Frequency. In Experiment 1, they walked a fixed path, with gait recordings, questionnaires, and body visualizations. In Experiment 2, they walked freely across campus routes with High/Low-Frequency soundtracks, followed by post-walk interviews using a novel spatial mapping tool linking body sensations to context. Results replicate the illusion outdoors, showing synchronization with prerecorded sounds as a viable alternative to real-time feedback, and revealing that contextual factors modulate illusion effects. We contribute insights and novel tools (prototype, spatial mapping method, and footstep soundbase) for studying multisensory body perception in everyday contexts.2026ADAmar D'Adamo et al.Universidad Carlos III de MadridMultisensory Fusion ExperienceEmotion Recognition & DetectionAffective Feedback & Emotion Regulation InterfacesCHI
Usage Matters: The Role of Frequency, Duration, and Experience in Presence Formation in Social Virtual RealityThe sense of presence is central to immersive experiences in Virtual Reality (VR), and particularly salient in socially rich platforms like social VR. While prior studies have explored various aspects related to presence, less is known about how ongoing usage behaviors shape presence in everyday engagement. To address this gap, we examine whether usage intensity, captured through frequency of use, session duration, and years of VR experience, predicts presence in social VR. A survey of 295 users assessed overall, social, spatial, and self-presence using validated scales. Results show that both frequency and duration consistently predict higher presence across all dimensions, with interaction effects indicating that frequent and extended sessions synergistically amplify the experience of “being there.” These effects were stable across age and gender. Our findings extend presence research beyond the laboratory by identifying behavioral predictors in social VR and offer insights for building inclusive environments that reliably foster presence.2026QCQijia Chen et al.University of HelsinkiSocial & Collaborative VRImmersion & Presence ResearchIdentity & Avatars in XRCHI
Social, Spatial, and Self-Presence as Predictors of Basic Psychological Need Satisfaction in Social VRExtensive research has examined presence and basic psychological needs (drawing on Self-Determination Theory) in digital media. While prior work offers hints of potential connections, we lack a systematic account of whether and how distinct presence dimensions map onto the basic needs of autonomy, competence, and relatedness. We surveyed 301 social VR users and analyzed using Structural Equation Modeling. Results show that social presence predicts all three needs, while self-presence predicts competence and relatedness, and spatial presence shows no direct or moderating effects. Gender and age moderated these relationships: women benefited more from social presence for autonomy and relatedness, men from self- and spatial presence for competence and autonomy, and younger users showed stronger associations between social presence and relatedness, and between self-presence and autonomy. These findings position presence as a motivational mechanism shaped by demographic factors. The results offer theoretical insights and practical implications for designing inclusive, need-supportive multiuser VR environments.2026QCQijia Chen et al.University of HelsinkiSocial & Collaborative VRImmersion & Presence ResearchIdentity & Avatars in XRCHI
Mirror Dwellers in Social VR: Investigating Reasons and Perception of Mirror WatchingIn social Virtual Reality (VR) environments, the significant trend of `mirror dwellers,' users who often use virtual mirrors to engage with their avatars, has emerged. This study examines discussions from the r/VRchat online community to explore the reasons for this behavior and how it is perceived within the broader community. Our findings highlight the critical role of mirrors in compensating for the sensory limitations of VR, particularly the lack of physical feedback. Users often turn to mirrors to view parts of their avatar that are not accessible from a first-person perspective. Additionally, our research uncovers that a limited Field-Of-View (FOV) hinders the development of a strong connection between users and their avatars, further driving the need for mirrors. However, while using mirrors to mitigate FOV and physical feedback limitations can be helpful, it may also disrupt social interaction in VR environments, as the excessive reliance on mirrors can hinder the social experience in VR for others. This research deepens our understanding of user behavior in social VR and provides insights that could guide future design improvements to enrich the overall user experience.2025QCQijia Chen et al.Perspectives on VRCSCW
Temporal Trajectories: Characterizing Somatic Experiences that Unfold Over Time The body technologies we design profoundly influence our somatic experiences, yet they are often evaluated through short-term or one-off studies. To design for sustained, longer-term engagements, we need to understand how somatic experiences evolve when people repeatedly interact with the same technology over time. With this goal, we report on two in-the-wild studies of body sonification, one with physically inactive individuals and another with professional dancers. For one month, participants used SoniBand, a movement sonification wearable, in their daily lives and shared their experiences with us through questionnaires and in-depth interviews. Drawing from the concept of trajectories, we identified four temporal patterns that characterized the participants' evolving experience with SoniBand: singular, sustained, deepening, and meandering. We unpack these temporal trajectories and reflect on the characteristics that may contribute to their emergence. Our findings offer insights for studying and designing future technologies that embrace the dynamic, evolving nature of people's somatic experiences.2025LVLaia Turmo Vidal et al.Vibrotactile Feedback & Skin StimulationHaptic WearablesFull-Body Interaction & Embodied InputDIS
Understanding "Mutes" in Social Virtual RealityIn social Virtual Reality (VR), particularly within VRChat, a significant group of users often referred to as ``mutes'' refrain from voice communication. This study analyzes 4212 discussion entries, including both original submissions and comments, from the r/VRchat subreddit to explore the experiences and reasons behind this practice. Our findings indicate that muteness is an integral aspect of social VR culture, yet mute users face challenges, including exposure to abusive behaviors and communication barriers in a fast-paced environment. Factors of social VR like harassment, heightened social anxiety from the immersive presence, and the complexities of identity management can discourage voice communication, leading many to adopt ``muteness'' as a response. This behavior can be seen within the broader context of social disability, challenging normative communication assumptions. We highlight the risks of generalizing marginalized communities and emphasize the need for further research to address and support the unique needs of these groups in social VR spaces.2025QCQijia Chen et al.University of Helsinki, Department of Computer ScienceSocial & Collaborative VRCyberbullying & Online HarassmentCHI
Imprinto: Enhancing Infrared Inkjet Watermarking for Human and Machine PerceptionHybrid paper interfaces leverage augmented reality to combine the desired tangibility of paper documents with the affordances of interactive digital media. Typically, virtual content can be embedded through direct links (e.g., QR codes); however, this impacts the aesthetics of the paper print and limits the available visual content space. To address this problem, we present Imprinto, an infrared inkjet watermarking technique that allows for invisible content embeddings only by using off-the-shelf IR inks and a camera. Imprinto was established through a psychophysical experiment, studying how much IR ink can be used while remaining invisible to users regardless of background color. We demonstrate that we can detect invisible IR content through our machine learning pipeline, and we developed an authoring tool that optimizes the amount of IR ink on the color regions of an input document for machine and human detectability. Finally, we demonstrate several applications, including augmenting paper documents and objects.2025MFMartin Feick et al.DFKI and Saarland University, Saarland Informatics Campus; MIT CSAILElectronic Textiles (E-textiles)On-Skin Display & On-Skin InputCHI
“I Felt Everyone Was a Streamer”: An Empirical Study on What Makes Avatar Collective Streaming EngagingA novel participatory livestreaming genre, Avatar Collective Streaming, is gaining traction. Beyond traditional audience participation mechanisms, such as chat messages or commands, these livestreams allow viewers to join, socially interact, and participate through avatars in a software-driven virtual scenario without requiring the presence of a human streamer. From observations of livestreaming sessions and interviews with regular users (n=23), we define the main features of this novel form of livestreaming and we analyze what makes it engaging for participants, as well as factors that limit the user experience. The use of avatars affords a strong sense of presence and participation, and together with the absence of a streamer, it shapes new forms of sociability, being together, and belonging. Challenges include repetitive content and overcrowding. We provide design implications for synchronous collective participation scenarios and opportunities for software-driven content generation.2024QCQijia Chen et al.Session 4f: Multiplayer Gaming and CommunicationCSCW
Body Sensations as Design Material: An Approach to Design Sensory Technology for Altering Body PerceptionSensory technologies alter how we perceive our body, which can have profound implications for multiple domains. Prior work has contributed a myriad of artefacts and evaluative studies, but we still lack design knowledge to design meaningful body perception alterations facilitated by sensory technologies. To address this gap, we draw from soma design to propose a methodological approach centered on body sensations as design material. We articulate our approach based on a project on co-designing wearables to alter body perception together with professional dancers. Our approach involves engaging participants in articulating and sharing body sensations to others, and exploring somatically sensory stimuli to co-design concepts for future technologies. We contribute experiential facets of body sensations, movement and sensory potentials to alter sensations, methods and design strategies, and a collection of ideas. Our work can be relevant to design communities interested in sensory technologies, perceptual alterations and body sensations as material.2024LVLaia Turmo Vidal et al.Shape-Changing Interfaces & Soft Robotic MaterialsDance & Body Movement ComputingDIS
Movits: a Minimalist Toolkit for Embodied SketchingWe present the design and evaluation of the Movits, a minimalist toolkit for embodied sketching design explorations. The toolkit includes technology probes featuring minimalist wearable digital units that support the hands-on exploration and design of movement-driven interactions using multisensory feedback. The Movits are self-contained and generate audiovisual or vibrotactile patterns in response to movement-based inputs. We present the theoretical and empirical grounding driving our design process. We discuss the findings of using the Movits during four co-design workshops with design students, technologists, dancers and physiotherapists, where they resulted in being generative and adaptable to a range of embodied design approaches. We contend that the Movits can be favourable for those interested in a holistic design approach to wearables in general and specifically for those targeting movement-based application domains.2024JVJosé Manuel Vega-Cebrián et al.Haptic WearablesFull-Body Interaction & Embodied InputDance & Body Movement ComputingDIS
SoniWeight Shoes: Investigating Effects and Personalization of a Wearable Sound Device for Altering Body Perception, Behavior and Emotion Changes in body perception influence behavior and emotion and can be induced through multisensory feedback. Auditory feedback to one's actions can trigger such alterations; however, it is unclear which individual factors modulate these effects. We employ and evaluate SoniWeight Shoes, a wearable device based on literature for altering one's weight perception through manipulated footstep sounds. In a healthy population sample across a spectrum of individuals (n=84) with varying degrees of eating disorder symptomatology, physical activity levels, body concerns, and mental imagery capacities, we explore the effects of three sound conditions (low-frequency, high-frequency and control) on extensive body perception measures (demographic, behavioral, physiological, psychological, and subjective). Analyses revealed an impact of individual differences in each of these dimensions. Besides replicating previous findings, we reveal and highlight the role of individual differences in body perception, offering avenues for personalized sonification strategies. Datasets, technical refinements, and novel body map quantification tools are provided.2024ADAmar D'Adamo et al.Universidad Carlos III de MadridVibrotactile Feedback & Skin StimulationFull-Body Interaction & Embodied InputFoot & Wrist InteractionCHI
Analysis and Implementation of Nanotargeting on LinkedIn Based on Publicly Available Non-PIIThe literature has shown that combining a few non-Personal Identifiable Information (non-PII) is enough to make a user unique in a dataset including millions of users. This work demonstrates that a combination of a few non-PII items can be activated to nanotarget users. We demonstrate that the combination of the location and 5 rare (13 random) skills in a LinkedIn profile is enough to become unique in a user base of ∼970M users with a probability of 75%. The novelty is that these attributes are publicly accessible to anyone registered on LinkedIn and can be activated through advertising campaigns. We ran an experiment configuring ad campaigns using the location and skills of three of the paper's authors, demonstrating how all the ads using >13 skills were delivered exclusively to the targeted user. We reported this vulnerability to LinkedIn, which initially ignored the problem, but fixed it as of November 2023.2024AMAngel Merino et al.Universidad Carlos III de MadridPrivacy by Design & User ControlIoT Device PrivacyContent Moderation & Platform GovernanceCHI
“I’d rather drink in VRChat”: Understanding Drinking in Social Virtual RealityDrinking in social VR has become popular, yet little is known about how users perceive and experience alcohol consumption while immersed in virtual spaces with others, as well as its potential harm and negative effects on their offline and online lives. To better understand this emerging phenomenon from the perspective of both drinkers and non-drinkers, we analyzed public discussions from the r/VRchat online community on users' perceptions, and experiences with alcohol consumption in social VR. Heavy drinking is prevalent. We find that VR drinkers feel less intoxicated, which makes them drink more without being aware of it. Anti-cybersickness designs may affect users' perception of vertigo, even if the vertigo is not caused by VR. We discuss how affordances that support meaningful activities (i.e., sense of presence, embodiment, and social interactions) exacerbate alcohol abuse. We propose implications for the design of safer social VR experiences for both drinkers and non-drinkers.2024QCQijia Chen et al.Helsinki UniversitySocial & Collaborative VRImmersion & Presence ResearchSleep & Stress MonitoringCHI
Design Resources in Movement-based Design Methods: a Practice-based CharacterizationMovement-based design methods are increasingly adopted to help design rich embodied experiences. While there are well-known methods in the field, there is no systematic overview to help designers choose among them, adapt them, or create their own. We collected 41 methods used by movement design researchers and employed a practice-based, bottom-up approach to analyze and characterize their properties. We found 17 categories and arranged them into five main groups: Design Resources, Activities, Delivery, Framing, and Context. In this paper, we describe these groups in general and then focus on Design Resources containing the categories of Movement, Space, and Objects. We ground the characterization with examples from empirical material provided by the design researchers and references to previous work. Additionally, we share recommendations and action points to bring these into practice. This work can help novice and seasoned design researchers who want to employ movement-based design methods in their practice.2023JVJosé Manuel Vega-Cebrián et al.Full-Body Interaction & Embodied InputDance & Body Movement ComputingDIS
Physical Warm-up Games. Exploring the Potential of Play and Technology DesignWarm-up games are widespread practices in multiple activities across domains, yet little scholarly work can be found about their role in physical training. Here, we study potential goals and benefits of warm-up games, and explore opportunities for technology inclusion through investigating a collection of warm-up games gathered: online, from a survey of online warm-up games curated, described, and used by Physical Education teachers; and in person, from an ongoing design research work as part of a technology-supported circus training course. Further, in the context of the latter, we conducted explorative design interventions, augmenting a range of the warm-up games with wearable technology. Our work surfaces major goals and benefits of warm-up games, which can be broadly classified as preparing participants physically, socially, and mentally. We also show how the inclusion of open-ended technology can support these goals and discuss broader opportunities for technology inclusion in warm-up games.2021ESElena Márquez Segura et al.Universidad Carlos III de MadridFull-Body Interaction & Embodied InputGamification DesignCHI
Exploring the Design Space of Immersive Social Fitness Games: The ImSoFit Games ModelThe design space of social exergames remains narrow despite the many benefits of playing and exercising together. Towards opening this design space, we followed a Research through Design (RtD) approach focused on exergames that can be fun and immersive social training experiences. Through embodied sketching activities with designers and 10 pairs of players, we explored future games for the ExerCube, an immersive exergame platform. Our work contributes with forms of intermediate-level knowledge: a design space model (the Immersive Social Fitness - ImSoFit - Games model); and a novel design vocabulary including new bodily orientations in co-located physical interaction. We illustrate their use and value scrutinizing three of our games and applying three analytical lenses to 1) understand how design choices impact how players move together; 2) evaluate design expectations and analyze players' behavior in relation to design choices; and 3) potentially extend the design space of immersive co-located social fitness games.2021ESElena Márquez Segura et al.Universidad Carlos III de MadridFull-Body Interaction & Embodied InputGame UX & Player BehaviorCHI
Programmable Smart Home Toolkits Should Better Address Households' Social NeedsEnd-user-programmable smart-home toolkits have engendered excitement in recent years. However, modern homes already cater quite well to users' needs, and genuinely new needs for smart-home automation seldom arise. Acknowledging this challenging starting point, we conducted a six-week in-the-wild study of smart-home toolkits with four carefully recruited technology-savvy families. Interleaved with free toolkit use in the home were several creativity workshops to facilitate ideation and programming. We evaluated use experiences at the end of the six weeks. Even with extensive facilitation, families faced difficulties in identifying needs for smart-home automation, except for social needs that emerged in all the families. We present analysis of those needs and discuss how end-user-programmable toolkits could better engage with both those household members who design new automated functions and those who merely `use' them.2021ASAntti Salovaara et al.Aalto University, University of HelsinkiSmart Home Interaction DesignSmart Home Privacy & SecurityCHI
SoniBand: Understanding the Effects of Metaphorical Movement Sonifications on Body Perception and Physical ActivityNegative body perceptions are a major predictor of physical inactivity, a serious health concern. Sensory feedback can be used to alter such body perception; movement sonification, in particular, has been suggested to affect body perception and levels of physical activity (PA) in inactive people. We investigated how metaphorical sounds impact body perception and PA. We report two qualitative studies centered on performing different strengthening/flexibility exercises using SoniBand, a wearable that augments movement through different sounds. The first study involved physically active participants and served to obtain a nuanced understanding of the sonifications’ impact. The second, in the home of physically inactive participants, served to identify which effects could support PA adherence. Our findings show that movement sonification based on metaphors led to changes in body perception (e.g., feeling strong) and PA (e.g., repetitions) in both populations, but effects could differ according to the existing PA-level. We discuss principles for metaphor-based sonification design to foster PA.2021JLJudith Ley-Flores et al.Universidad Carlos III de MadridVibrotactile Feedback & Skin StimulationFitness Tracking & Physical Activity MonitoringCHI
The Design Space of Wearables for Sports and Fitness PracticesThe growing interest in wearables for sports and fitness calls for design knowledge and conceptualizations that can help shape future designs. Towards that end, we present and discuss a design space of wearables for these practices, based on a survey of previous work. Through a thematic analysis of 47 research publications in the domain, we surface core design decisions concerning wearability, technology design, and wearable use in practice. Building on these, we show how the design space takes into account the goals of introducing technology, that design decisions can be either directly designed, or left open for appropriation by end-users; and the social organization of the practice. We characterize prior work based on the design space elements, which yields trends and opportunities for design. Our contributions can help designers think about key design decisions, exploit trends and explore new areas in the domain of wearables for sports and fitness practices.2021LVLaia Turmo Vidal et al.Uppsala UniversityFitness Tracking & Physical Activity MonitoringSmartwatches & Fitness BandsCHI
Chasing Play Potentials in Food Culture: Learning from Traditions to Inspire Future Human-Food Interaction DesignIn this pictorial, we turn to culture and traditions to present an annotated portfolio of play-food potentials, i.e. interesting design qualities and/or interaction mechanisms that could help promote playful and social engagement in food practices. Our portfolio emerged from a one-day workshop where we played with and analyzed a collection of 27 food traditions from diverse cultural backgrounds and historical periods. We highlight play forms and experiential textures that are underexplored in Human-Food Interaction (HFI) research. Our contribution is intended to inspire designers to broaden the palette of play experiences and emotions embraced in HFI.2020FBFerran Altarriba Bertran et al.Gamification DesignFood Culture & Food InteractionDIS