This paper reports on a between-subject, comparative online study of three information visualization demonstrators that each displayed the same dataset by way of an identical scatterplot technique, yet were different in style in terms of visual and interactive embellishment. We validated stylistic adherence and integrity through a separate experiment in which a small cohort of participants assigned our three demonstrators to predefined groups of stylistic examples, after which they described the styles with their own words. From the online study, we discovered significant differences in how participants execute specific interaction operations, and the types of insights that followed from them. However, in spite of significant differences in apparent usability, enjoyability and usefulness between the style demonstrators, no variation was found on the self-reported depth, expert-rated depth, confidence or difficulty of the resulting insights. Three different methods of insight analysis have been applied, revealing how style impacts the creation of insights, ranging from higher-level pattern seeking to a more reflective and interpretative engagement with content, which is what underlies the patterns. As this study only forms the first step in determining how the impact of style in information visualization could be best evaluated, we propose several guidelines and tips on how to gather, compare and categorize insights through an online evaluation study, particularly in terms of analyzing the concise, yet wide variety of insights and observations in a trustworthy and reproducable manner.

We examined gamma-band magnetoencephalographic (MEG) activity in humans manipulating attention to visual stimuli by auditory distractors. After exposure to both visual and auditory noise (a baseline), subjects attended to the first of two stimuli (either regular motion of bars or a tone sequence) presented asynchronously, and responded to its offset. A spectral power analysis revealed an increased, relative to baseline, 40 Hz MEG response to attended coherent motion. The enhancement occurred within the initial 50-250 ms from motion onset over modality-specific (occipital) cortices. The increase was not observed when attention was captured by auditory distractors. Our findings suggest that 40 Hz activity in the human visual cortex is related to integration of featural information that is supported by attention.

We present a study and reflection about the role and use of smartphone technology for a large-scale musical performance involving audience participation. We evaluated a full design and development process from initial ideation to a final performance concept. We found that the smartphone became the design tool, the technical device and the musical instrument at the same time. As a technical device that uses ultrasound communication as interaction technique, the smartphone became inspirational for the artist's creative work. In aiming to support the artist, we observed pervasive importance of retaining artistic control to realise artistic intent. This concerns the co-design process and the resulting concept of audience participation and supports recommendations for such participatory work.

We discuss a setup for technology-mediated audience participation (TMAP)in live music using smartphones and highfrequency sound IDs in a playful setting. The audience needs to install a smartphone app. Using high-frequency sound IDs music samples and colors can be triggered on the audience's smartphones without the need to have an internet connection. The resulting soundscape is determined by the samples and parameters selected by the artist as well as by the location audience members choose in the performance space. We present the technical basis and iterative explorative design process of such a system for TMAP. The learnings from the perspective of musicians were technical requirements such as low latency, reliability, as well as increasing the number of possible sound samples and sound quality and we further present learnings on creating systems for TMAP from technical and creative perspectives.

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