Sound, Music, Language, and Human Communication: Acoustic Nudges in Sound-Mediated Interaction

All rights remain with the authors under the Creative Commons Attribution 4.0 International License (CC BY 4.0). Proc. of the 17th Int. Symposium on Computer Music Multidisciplinary Research, London, United Kingdom, 2025 Sound, Music, Language, and Human Communication: Acoustic Nudges in Sound-Mediated Interaction Nami Arimitsu [0000-0003-3662-4379] Toyo University, 5-28-20, Hakusan, Bunkyo, Tokyo, 112-8606, Japan [email protected] Abstract. Communication has long been regarded primarily as a linguistic act. However, human interaction is also profoundly shaped by nonverbal elements, with sound and music serving as especially powerful communication channels that guide behavior in subtle and culturally embedded ways. This paper proposes the concept of acoustic nudge to describe instances where sound encourages, shapes, or redirects actions without explicit verbal commands. Everyday auditory practices—from station departure melodies that prompt passengers to hurry, to temple bells marking time and order— illustrate how sound mediates collective behavior. Brown and Levinson [1] explain how indirectness reduces face-threatening acts and minimizes resistance. This paper argues that such an effect of indirectness can also be seen in nonverbal sound cues. Gibson [2] describes affordances as environmental cues that suggest actions, while Norman [4] extends this to design, showing how interfaces guide users through implicit signals. Thaler and Sunstein [6] define a nudge as “any aspect of the choice architecture that alters people’s behavior in a predictable way without forbidding any options or significantly changing their economic incentives” (p. 6). In other words, a nudge steers behavior while preserving freedom of choice. Schafer [7] highlights that soundscapes carry shared cultural meanings that frame interpretation. Building on these theories, I examine auditory practices in urban Japan to show how culturally embedded sounds function as indirect yet powerful cues that promote awareness and guide behavior, in some cases, more effectively than verbal instruction. Framing such practices as acoustic nudges offers a new lens for understanding human–environment interaction and has potential applications in soundscape design, human–computer interaction, public policy, and user experience research. Keywords: acoustic nudge, auditory ecology, affordance, politeness. 1 Introduction 1.1 Background: Nudge theory and the soundscape gap Communication has long been regarded primarily as a linguistic act. However, human social interaction is also profoundly shaped by nonverbal elements, with sound Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 177 N. Arimitsu and music serving as especially powerful communication channels that influence behavior in subtle and culturally embedded ways. This study proposes the concept of “acoustic nudge” to explain the mechanism by which sound encourages human behavior without using explicit linguistic commands. Nudge theory (Thaler & Sunstein [6]) has been widely accepted as a design principle that guides people’s behavior in desirable directions without restricting their options. In Japan, Ohtake [5] has demonstrated the effectiveness of nudges in contexts such as disaster evacuation and public health. These studies have clarified the effectiveness of nudges in the fields of public policy and crisis response, but most of them are based on socio-psychological or behavioral economic interventions, and the perspective of sound and music, that is, the soundscape, has not been sufficiently examined. 1.2 Research novelty and objectives The novelty of my study lies in the following. That is, while previous studies have focused on nudges in policy and social behavior, my research conceptualizes sound as a “culturally shared signal” and theorizes the phenomenon in which it induces behavior without explicit linguistic commands as “acoustic nudge.” The purpose is to connect existing nudge research and soundscape studies, and to present acoustic nudge as a new analytical framework. In the Japanese context, for example, Hiramatsu [3] provides a comprehensive review of soundscape studies, in which he also discusses sounds presented in public spaces. There, numerous studies are introduced, such as those showing that sign sounds and auditory signals serve to attract attention and guide behavior, that background music divides evaluation between comfort and noise as a cultural phenomenon, and that public announcements have historically been treated as social problems. These discussions demonstrate that sound in Japan is not merely a physical phenomenon but rather has been endowed with meaning in social and cultural contexts, guiding people’s behavior and cognition. However, while previous research has focused on aspects such as impression evaluation and social acceptance of sounds, the mechanism by which sound guides people’s decision-making and behavioral choices as a “nudge” has not been sufficiently organized. My study is novel in this respect, aiming to theoretically redefine sound by connecting it to the perspective of behavioral economics, while also building on the insights of Hiramatsu [3]. In addition, it incorporates findings from linguistic research on politeness, thereby framing acoustic nudges not only as behavioral mechanisms but also as communicative strategies embedded in society. This perspective highlights the originality of treating sound through the lens of nudge theory while simultaneously situating it within the broader domain of social communication. 2 Methodology 2.1 Definition of acoustic nudge This study defines acoustic nudge as “an auditory stimulus that unconsciously and automatically guides human attention, emotion, and behavior.” By adopting this Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 178 Sound, Music, Language, and Human Communication definition, the study establishes a theoretical domain distinct from the conventional concept of affordance. Affordances are generally understood as environmental cues that present action possibilities (e.g., a chair affords sitting), whereas nudges are characterized by their capacity to guide actual behavior (e.g., a train departure melody prompting passengers to hurry). The distinction is threefold: nudges not only indicate potential actions but subtly steer behavior in a particular direction, they often operate unconsciously and thus minimize resistance, and they are culturally embedded, relying on shared auditory signals that are immediately intelligible within a given society. Taken together, these features distinguish acoustic nudges as mechanisms that move beyond framing possibilities to actively guiding choices and conduct in everyday contexts. 2.2 Research framework This study aims to clarify the effectiveness of acoustic nudges through case analysis of urban practices in Japan. Each case is examined from four analytical perspectives. First, cultural embeddedness refers to the degree to which the sound has been internalized and shared within society. Second, low resistance indicates whether the auditory stimulus is accepted without evoking a sense of coercion or discomfort. Third, effectiveness of behavioral guidance assesses whether the sound successfully prompts people to take desirable actions in a natural and intuitive manner. Fourth, contextual appropriateness and sustainability evaluate whether the auditory cue fits the situational context and whether it can function consistently over the long term. By applying this analytical framework, the study demonstrates that acoustic nudges are not limited to the evaluation of “impressions of sound,” but rather illustrate how sound can serve as a form of social communication that parallels language. In doing so, it highlights the behavioral-economic effects of auditory cues, thereby providing a theoretical foundation for understanding sound as an agent that guides attention, emotion, and action in everyday life. 3 Case studies 3.1 Closing-time melodies (Auld Lang Syne and others) In this section, five cases of acoustic nudges in Japan are examined, each analyzed from the perspectives of cultural embeddedness, low resistance, effectiveness of behavioral guidance, and contextual appropriateness and sustainability. These cases demonstrate how sound embedded in social contexts can subtly direct human behavior. One of the most familiar examples of acoustic nudges in Japan is the use of closingtime melodies in public spaces. The song Hotaru no Hikari (“Light of the Fireflies”) is widely recognized as music associated with graduation ceremonies and the closing of shops. For many Japanese people, the melody symbolizes “an ending” or “parting,” and thus functions as a culturally shared auditory signal. Its original tune, Auld Lang Syne, is traditionally sung in Scotland as a New Year’s song, yet in Japan it has instead been reinterpreted as a sign marking closure or the transition toward departure. Similarly, the Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 179 N. Arimitsu second movement (“Goin’ Home”) of Dvořák’s Symphony No. 9 (From the New World) is sometimes played in public spaces to mark the close of business for the day, evoking the sense of “returning home.” This is not universal, but in my local library, for instance, Goin’ Home was once used as the closing-time melody. Today it has been replaced by a gentle tune composed by a local musician, reflecting how music can not only guide behavior but also contribute to the identity of a place. Yet even after this change, the sudden appearance of music in an otherwise silent library space continues to function as an unmistakable cue, signaling to users, without words, that “it is time to leave.” This is typically followed by an announcement such as “Please complete your borrowing soon,” but not by an explicit command to “exit.” In this way, music functions as a polite and culturally resonant cue, gently guiding people’s behavior without verbal imposition. From the four analytical perspectives proposed in this study, this case may be summarized as follows: (1) Cultural embeddedness: The melodies are deeply tied to collective memories, as many Japanese have repeatedly heard them in schools or shops, and they are instantly associated with “ending” or “returning home.” (2) Low resistance: Instead of directly instructing people to leave, the familiar tunes softly encourage exit, reducing any sense of coercion or discomfort. (3) Effectiveness of behavioral guidance: Once the music begins, people naturally start to tidy up or complete payments, leading to an orderly transition without confusion. (4) Contextual appropriateness and sustainability: These melodies have been in widespread use for generations across Japan and are likely to remain established as cultural conventions. Taken together, these features make closing-time melodies more than just background music. They represent a classic case of the acoustic nudge, elegantly and effectively directing behavior without words. 3.2 Station melodies (Yamanote Line departure tunes) On Tokyo’s Yamanote Line, some stations have their own departure melody, functioning as a distinctive auditory sign for passengers. At Ikebukuro Station, for instance, the jingle of the electronics retailer Bic Camera is used, while at Takadanobaba Station the theme song of Osamu Tezuka’s iconic manga and anime Astro Boy (Tetsuwan Atom) is played. These melodies are widely familiar across generations through television commercials, manga, and anime, to the extent that many passengers can “sing along” in their heads even without lyrics. Unlike buzzers or sirens, which can feel harsh or coercive, these short melodic cues allow passengers to intuitively grasp that only a few seconds remain before departure. Although the music played in stations is purely instrumental and carries no lyrics, if the tune is familiar, passengers know in their minds how the melody will unfold. As a result, they can anticipate how much time is left before the doors close and the train departs. Thus, they naturally quicken their pace and complete boarding efficiently, without experiencing psychological pressure. Even at stations that do not use well-known Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 180 Sound, Music, Language, and Human Communication songs but instead employ their own original melodic signals, listeners can still imagine whether the tune is continuing or approaching a musical cadence, that is, a musical closing point. This unfolding structure enables passengers to sense the remaining time in a way that a simple buzzer or siren cannot. I argue that this is precisely what makes station melodies unique compared with mere alarm sounds. Beyond their immediate functional role, station melodies also help strengthen ties to local culture. As shown above, some stations adopt melodies that evoke nearby cultural symbols or well-known enterprises with strong local connections, creating a sense of place and identity for those stations. From the analytical framework of this study, this case can be interpreted as follows: (1) Cultural embeddedness: Through in-store repetition of corporate theme songs, as in the case of Bic Camera, shoppers become so accustomed to the melody that they memorize it. In addition, such melodies are widely recognized and shared across multiple generations through television commercials, manga, and anime. (2) Low resistance: By using short melodies rather than harsh buzzers or sirens, the cues softly draw attention without imposing a psychological burden. (3) Effectiveness of behavioral guidance: The ending of the melody serves as a clear signal, prompting passengers to act swiftly and complete boarding naturally. (4) Contextual appropriateness and sustainability: The melodies contribute to station identity, function as tourist resources, and are likely to remain sustainable due to their strong ties to regional culture. Taken together, Yamanote Line station melodies exemplify how culturally embedded sounds can simultaneously manage flow, reduce resistance, and enrich the social identity of public spaces, making them an example of the acoustic nudge in practice. 3.3 Taxi Seatbelt Chime (Song by Yumi Matsutoya) In some Japanese taxis today, when passengers fail to fasten their seatbelts, instead of a warning buzzer, a music-box style version of Yumi Matsutoya’s (formerly Yumi Arai) song “Yasashisa ni Tsutsumaretanara” (Wrapped in Kindness) is played. Originally released in 1974, the song gained renewed attention in 1989 when it was used as the ending theme of Studio Ghibli’s film Kiki’s Delivery Service, and since then it has been widely familiar across generations, including among younger audiences. Many passengers can recall the lyrics upon hearing only the melody, indicating the song’s deep social penetration. The tune thus functions as more than a simple signal: it evokes feelings of warmth, kindness, reassurance and even happiness. In some cases, the song’s title phrase, “being wrapped in kindness,” may even be interpreted metaphorically as being safely “wrapped” by the protection of a seatbelt. (1) Cultural embeddedness: This gentle and heartwarming song is widely known in Japan and across generations, with shared associations of warmth, kindness and reassurance. Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 181 N. Arimitsu (2) Low resistance: Unlike a buzzer sound, which carries a sense of compulsion, this soft and gentle music encourages passengers to fasten their seatbelts without psychological discomfort. (3) Effectiveness of behavioral guidance: The continued playing of the melody creates psychological awareness, prompting passengers to “fasten quickly” without inducing negative feelings. (4) Contextual appropriateness and sustainability: With growing social awareness of safety, such gentle design strategies are likely to remain widely accepted in Japanese society. In this way, the taxi seatbelt chime functions not as a “warning sound” but as a “gentle cue,” making effective use of a culturally familiar song to minimize resistance while successfully guiding passengers toward safe behavior. 3.4 Disaster Warning Sounds Japan is a country with long experience of natural disasters such as earthquakes and tsunamis, and distinctive warning systems have been carefully designed for these emergencies. For example, on television, alerts are displayed in large fonts with high-contrast colors, accompanied by sounds designed to trigger a strong physiological reaction, drawing people’s attention at once and directing them toward the news broadcast. Similarly, when people are using their mobile phones on trains, many devices may simultaneously emit the emergency earthquake alert at maximum volume. This is accompanied by a repeated voice announcement saying “Jishin desu” (“An earthquake is occurring”), indicating that a tremor of a significant scale is expected nearby. At the very moment people hear this distinctive sound, they instinctively recognize that they must take protective action to safeguard their lives. The sound has a strong physiological impact and functions as an unmistakable sign demanding immediate attention. (1) Cultural embeddedness: Based on past experiences of earthquakes and tsunamis, there is a strong shared understanding that the alert signifies the need to take immediate protective action. (2) Low resistance: Although the sound is coercive and conveys extreme urgency, it is socially justified under the imperative of “saving lives.” Indeed, its very unpleasant nature enhances its effectiveness in capturing attention. Even if, on occasion, the predicted danger does not fully materialize, it is still considered safer to take precautionary action. (3) Effectiveness of behavioral guidance: Once the alert sounds, people promptly shift to evacuation or precautionary behaviors, contributing to the reduction of overall social risk. (4) Contextual appropriateness and sustainability: The system is tailored to Japan’s specific natural disaster risks and has been continuously refined and institutionalized, ensuring its sustainability over the long term. In this way, disaster warning sounds operate as acoustic nudges that, while accompanied by psychological pressure, are widely accepted by society. Supported by cultural Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 182 Sound, Music, Language, and Human Communication and institutional contexts, they represent carefully designed mechanisms that immediately and effectively direct people’s behavior in times of crisis. 3.5 Foreign Language Music in Cafés (e.g., Bossa Nova) In Japanese cafés and commercial spaces, it is common to hear foreign-language music in English, French, Portuguese, and other languages whose lyrics are not easily understood by most customers. For example, the light and gentle rhythms of bossa nova sung in Portuguese create an atmosphere that allows people to momentarily forget their everyday lives, thereby enhancing the sense of comfort within the space. Precisely because the lyrics are unintelligible to most Japanese listeners, the songs are received as “relaxing and comfortable sound” rather than verbal semantic content, which brings a unique sense of relaxation and cognitive ease, allowing listeners to enjoy the sound without the effort of processing meaning. (1) Cultural embeddedness: Among many Japanese people, there exists a shared understanding that foreign-language lyrics, precisely because they are incomprehensible, are best appreciated as pleasant background music. (2) Low resistance: The music carries no coercive or explicit message and is naturally accepted as an acoustic environment that softens and enriches the atmosphere. (3) Effectiveness of behavioral guidance: By generating a relaxed ambience, the music encourages customers to linger longer in the café and to make additional purchases. (4) Contextual appropriateness and sustainability: Foreign-language music has become deeply rooted in Japanese café culture, where it continues to function as a contextually appropriate and enduring design that promotes extended stays. In this way, foreign-language music functions less as a carrier of meaning and more as an acoustic atmosphere, serving as a culturally shared device for creating comfortable spaces. It thus operates as an acoustic nudge that gently guides human behavior without exerting any sense of coercion. 4 Discussion and Conclusion The five case studies presented in this paper demonstrate that culturally embedded auditory stimuli can function as “acoustic nudges,” guiding human behavior without invoking a sense of coercion. Long-established practices such as closing melodies in shops or departure tunes on train platforms are rooted in cultural memory shared across generations, allowing them to serve as immediately recognizable signals. By contrast, newer practices such as seatbelt reminder melodies in taxis or the use of foreign-language music in cafés create feelings of reassurance and comfort in daily life, reflecting the emergence of acoustic nudges in response to social change and evolving lifestyles. In the case of disaster alerts, which involve high urgency, the auditory cues carry strong Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 183 N. Arimitsu psychological pressure but are nonetheless widely accepted as culturally justified signals, capable of prompting immediate protective actions. What unites these examples is the way sound operates not merely as background or physical stimulus, but as a form of nonverbal communication embedded in social and cultural contexts. The meanings carried by music and sound often guide behavior in ways that are more intuitive and less resistant than verbal commands. Thus, the concept of acoustic nudge provides a theoretical framework that bridges soundscape research, behavioral economics, and communication studies, revealing sound as a mechanism that unconsciously guides human attention, emotion, and action. From a linguistic perspective, acoustic nudges can also be interpreted as an extension of politeness strategies (Brown & Levinson [1]). Instead of issuing direct commands, they rely on indirect and culturally shared auditory cues that minimize face-threatening acts and gently encourage behavior. This suggests that sound itself can embody a form of politeness, extending the insights of linguistic pragmatics into the auditory domain. Taken together, the case studies illustrate the diverse forms of culturally grounded acoustic nudges and underscore the profound role of sound in shaping human conduct. More than functional signals, these auditory practices demonstrate how societies embed meaning, memory, and emotion into sound, allowing it to steer behavior with subtlety, offering what verbal communication alone cannot provide. Ultimately, the framework of acoustic nudge highlights sound as a fundamental force in human life, an invisible yet pervasive medium that links culture, behavior, and communication, reminding us that human life is guided not only by words, but also by the resonances that permeate our shared environments. Disclosure of Interests. The author has no competing interests to declare that are relevant to the content of this article. References 1. Brown, P., & Levinson, S. C. (1987). Politeness: Some Universals in Language Usage. Cambridge University Press, Cambridge. 2. Gibson, J. J. (1979). The Ecological Approach to Visual Perception. Houghton Mifflin, Boston. 3. Hiramatsu, K. (2006). A Review of Soundscape Studies in Japan, Acta Acustica united with Acustica, 92, 857-864. 4. Norman, D. A. (2013). The Design of Everyday Things (Revised and Expanded Edition). Basic Books, New York. 5. Ohtake, F. (2022). Can nudges save lives?, The Japanese Economic Review, 73, 245–268. https://doi.org/10.1007/s42973-021-00095-7 6. Thaler, R. H., & Sunstein, C. R. (2008). Nudge: Improving Decisions About Health, Wealth, and Happiness. Yale University Press, New Haven & London. 7. Schafer, R. M. (1994). The Soundscape: Our Sonic Environment and the Tuning of the World. Destiny Books, Rochester. Proc. of the 17th International Symposium on CMMR, London, UK, Nov. 3-7, 2025 184