Sounds Uncertain: Exploring the Affective Aspects of Sonification for Uncertainty Visualization

Affective visualization combines data representation with emotional context to influence how users perceive, interpret, and engage with information. While visual channels like color and motion are frequently studied, alternative modalities such as the auditory channel remain largely underexplored in uncertainty visualization. This paper investigates how sonification can communicate the affective dimensions of data uncertainty and neutrality through a co-design user study.

The authors conducted a user study with 21 non-expert participants using a custom interactive study tool. Participants were tasked with creating two distinct sonifications to accompany a temperature visualization: an uncertain sonification for forecasted future temperatures and a neutral sonification for historical recorded temperatures. The tool allowed users to manipulate parameters such as musical instruments, volume, pitch, white noise, amplitude modulation, looping, and frequency filtering. Throughout the process, researchers recorded participant interactions, audio, and talk-aloud protocol transcripts, which were analyzed using reflexive thematic analysis.

The qualitative and quantitative analysis revealed clear distinctions in how participants translated uncertainty and neutrality into auditory parameters. Uncertainty was predominantly linked to wavy auditory qualities and an ominous sentiment, reflecting feelings of anxiety and risk associated with unpredictable future outcomes. In contrast, neutrality was consistently associated with clear, stable, and relaxing auditory qualities that felt calm and unobtrusive. Participants utilized parameters like tremolo, looping, and white noise to evoke tension for uncertainty, while opting for clean tones to represent baseline historical data.

These insights demonstrate that sonification can effectively enrich uncertainty visualizations by adding an affective layer that aligns with human psychological responses to unknown information. By understanding these intuitive auditory mappings, visualization designers can better incorporate sound to convey data uncertainty without unintentionally triggering unwanted emotional responses.