Currently the field of brain-computer interfacing is increasingly focused on developing usable brain-computer interfaces (BCIs) to better ensure technology transfer and acceptance. Many studies have investigated the usability of BCI applications as a whole. Here we aim to investigate one specific component of an electroencephalogram (EEG)-based BCI system: the acquisition component. This study compares on the usability of three different EEG headsets in the context of a P300-based BCI application for communication. Thirteen participants took part in a within-subject experiment. Participants were randomly given a Biosemi, Emotiv EPOC or g.Sahara headset. After every session offline classification accuracy (efficacy) was calculated and usability factors (perceived efficiency and user satisfaction) were measured using questionnaires. The 32-channel Biosemi headset offered the highest accuracy (88.5%) compared with the 8-channel g.Sahara (62.7%) and the 14-channel Emotiv (61.7%). There was no difference in accuracy between the Biosemi and the g.Sahara when comparing the same 8 channels. The Biosemi and g.Sahara were rated as more comfortable than the Emotiv. The Emotiv was rated as best for aesthetics. System setup time was highest for the Biosemi headset when compared with the g.Sahara and the Emotiv. Without information about the effectiveness, participants preferred the Emotiv. We recommend the use of a gelled headset for applications which require high accuracy and efficiency and water-based or dry headsets when aesthetics, easy setup and fun are important. RESEARCH HIGHLIGHTS• This systematic within-subject study compares the usability of three electroencephalogram systems in a classical brain-computer interfaces paradigm. • Conventional gelled electrodes were found to be more effective and efficient than water-based electrodes.• Participants valued their appearance with the system and ease of setup higher than comfort.

In recent years, many different studies regarding Co-located Augmented Play-spaces (CAPs) have been published in a wide variety of conferences and journals. We present an overview. The work presented in these papers includes end user's perspectives as well as researcher's perspective. We place these within four aspects in this review: (1) Argumentation, the underlying reasons or the higher end goals to investigate interactive play from a user's perspective, (2) Systems, the kind of systems that are created, this includes their intended use which fits the end user's perspective, (3) Evaluation, the way in which the researchers evaluate the system, (4) Contribution, the goal of the studies from the researcher's perspective; what does the study contribute to the research community. CAPs are often multimodal in nature; this survey pays attention to the multimodal characteristics in relation to all four aspects. This overview contributes a clearer view on the current literature, points out where new opportunities lie, and hands us the tools for what we think is important: bringing the end-user and research perspective together in intervention based evaluations. In short, this paper discusses CAPs: their past, the present, and the perspectives.

This paper presents work in the field of distributed exertion games, which are controlled by moving the body. People play these games together while being located at different places in the world. The novel contribution of this paper is the introduction of distributed team play in which both collocated and distributed players participate. In our Distributed Interactive Pong Playground (DIPP) players bounce a ball towards a goal by moving, walking, and running around in a 5.3 by 5.3 m interactive playground. We investigate whether we can increase coordination in movement between players by changing the game to enforce teamwork. This was done by letting the players in a team control one end each of a shared paddle, as opposed to both players having separate paddles. Although the results should be taken with care, the comparisons do indicate that we could steer the amount of coordination between players in this way. Furthermore, we investigated the effect of distributed team play on the level of coordination. The results indicate that coordination goes down if the teammate is at another location. In this distributed team setting, enforced team work through a connected paddle still leads to a higher level of measured coordination. In contrast, our current analysis of self-reported social presence did not show a clear difference, not favoring enforced team work nor a particular team distribution. With the DIPP and this study we provide a new direction for distributed exertion games with a focus on aspects of team play.