Hayrettin Gürkök

Brain-Computer Interfacing and Games

Recently research into Brain-Computer Interfacing (BCI) applications for healthy users, such as games, has been initiated. But why would a healthy person use a still-unproven technology such as BCI for game interaction? BCI provides a combination of information and features that no other input modality can offer. But for general acceptance of this technology, usability and user experience will need to be taken into account when designing such systems. Therefore, this chapter gives an overview of the state of the art of BCI in games and discusses the consequences of applying knowledge from Human-Computer Interaction (HCI) to the design of BCI for games. The integration of HCI with BCI is illustrated by research examples and showcases, intended to take this promising technology out of the lab. Future research needs to move beyond feasibility tests, to prove that BCI is also applicable in realistic, real-world settings.

Brain-Computer Interfaces for Multimodal Interaction: A Survey and Principles

For decades, brain–computer interfaces (BCIs) have been used for restoring the communication and mobility of disabled people through applications such as spellers, web browsers, and wheelchair controls. In parallel to advances in computational intelligence and the production of consumer BCI products, BCIs have recently started to be considered as alternative modalities in human–computer interaction (HCI). One of the popular topics in HCI is multimodal interaction (MMI), which deals with combining multiple modalities in order to provide powerful, flexible, adaptable, and natural interfaces. This article discusses the situation of BCI as a modality within MMI research. State-of-the-art, real-time multimodal BCI applications are surveyed in order to demonstrate how BCI can be helpful as a modality in MMI. It is shown that multimodal use of BCIs can improve error handling, task performance, and user experience and that they can broaden the user spectrum. The techniques for employing BCI in MMI are described, and the experimental and technical challenges with some guidelines to overcome these are shown. Issues in input fusion, output fission, integration architectures, and data collection are covered.

Experiencing BCI Control in a Popular Computer Game

Brain-computer interfaces (BCIs) are not only being developed to aid disabled individuals with motor substitution, motor recovery, and novel communication possibilities, but also as a modality for healthy users in entertainment and gaming. This study investigates whether the incorporation of a BCI in the popular game World of Warcraft (WoW) has effects on the user experience. A BCI control channel based on parietal alpha band power is used to control the shape and function of the avatar in the game. In the experiment, participants (n=42) , a mix of experienced and inexperienced WoW players, played with and without the use of BCI in a within-subjects design. Participants themselves could indicate when they wanted to stop playing. Actual and estimated duration was recorded and questionnaires on presence and control were administered. Afterwards, oral interviews were taken. No difference in actual duration was found between conditions. Results indicate that the difference between estimated and actual duration was not related to user experience but was person specific. When using a BCI, control and involvement were rated lower. But BCI control did not significantly decrease fun. During interviews, experienced players stated that they saw potential in the application of BCIs in games with complex interfaces such as WoW. This study suggests that BCI as an additional control can be as much fun and natural to use as keyboard/mouse control, even if the amount of control is limited.

Evaluating a multi-player brain-computer interface game: challenge versus co-experience

Brain–computer interfaces (BCIs) have started to be considered as game controllers. The low level of control they provide prevents them from providing perfect control but allows the design of challenging games which can be enjoyed by players. Evaluation of enjoyment, or user experience (UX), is rather a new practice with BCI applications. The UX of multi-player BCI games, or co-experience, is especially scarcely assessed. In the study we report in this paper, we relied on observation analysis of social interaction to infer co-experience of pairs of players while they were playing a collaborative multi-player game using BCI. To investigate the effect of perceived level of control on co-experience, we compared BCI control to a more reliable mouse control. In order to investigate the co-experience related factors beyond the level of control, we compared BCI control to an equally reliable control mechanism. Our results show that low level of control dampened collaborative interaction while enhancing emotional interaction within pairs of players. Thus, the challenge of playing a computer game using BCI can influence the co-experience.

Social Interaction in a Cooperative Brain-computer Interface Game

Does using a brain-computer interface (BCI) influence the social interaction between people when playing a cooperative game? By measuring the amount of speech, utterances, instrumental gestures and empathic gestures during a cooperative game where two participants had to reach a certain goal, and questioning participants about their own experience afterwards this study attempts to provide answers to this question. The results showed that social interaction changed when using a BCI compared to using a mouse. There was a higher amount of utterances and empathic gestures. This indicates that the participants reacted more to the higher difficulty of the BCI selection method. Participants also reported that they felt they cooperated better during the use of the mouse.

Perspectives on user experience evaluation of brain-computer interfaces

The research on brain-computer interfaces (BCIs) is pushing hard to bring technologies out of the lab and into society and onto the market. The nascent merge between the field of BCI and humancomputer interaction (HCI) is paving the way for new applications such as BCI-controlled gaming. The evaluation or success of BCI technologies is often based on how accurate the control of a user is with the technology. However, while this is still key to its usability, other factors that influence the user experience (UX) can make or break a technology. In this paper we first review studies which investigated user experience with BCIs. Second, we will discuss how HCI approaches can contribute to the evaluation of BCIs. Finally, we propose to develop a standardized questionnaire for evaluating BCIs for entertainment purposes.

Brain-Computer interface games: towards a framework

The brain-computer interface (BCI) community started to consider games as potential applications while the games community started to consider BCI as a game controller. However, there is a discrepancy between the BCI games developed by the two communities. In this paper, we propose a preliminary BCI games framework that we constructed with respect to the research conducted in both the BCI and the games communities. Developers can situate their BCI games within this framework and benefit from the guidelines we provide and also extend the framework further.

Brain–Computer Interfaces and User Experience Evaluation

The research on brain–computer interfaces (BCIs) is pushing hard to bring technologies out of the lab, into society and onto the market. The newly developing merge of the field of BCI with human–computer interaction (HCI) is paving the way for new applications such as BCI-controlled games. The evaluation or success of BCI technologies is often based on how accurate the control of a user is over the technology. However, while this is still key to its usability, other factors that influence the user experience (UX) can make or break a technology. In this paper we first review studies that investigated user experience with BCIs. Second, we will discuss how methods from the field of HCI can contribute to the evaluation of BCIs. From experience drawn from two case studies we provide recommendations for evaluating BCIs.

Improving BCI performance after classification

Brain-computer interfaces offer a valuable input modality, which unfortunately comes also with a high degree of uncertainty. There are simple methods to improve detection accuracy after the incoming brain activity has already been classified, which can be divided into (1) gathering additional evidence from other sources of information, and (2) transforming the unstable classification results to be more easy to control. The methods described are easy to implement, but it is essential to apply them in the right way. This paper provides an overview of the different techniques, showing where to apply them and comparing the effects. Detection accuracy is important, but there are trade-offs to consider. Future research should investigate the effectiveness of these methods in their context of use, as well as the optimal settings to obtain the right balance between functionality and meeting the users expectations for maximum acceptance.

Evaluating user experience in a selection based brain-computer interface game a comparative study: a comparative study

In human-computer interaction, it is important to offer the users correct modalities for particular tasks and situations. Unless the user has the suitable modality for a task, neither task performance nor user experience can be optimised. The aim of this study is to assess the appropriateness of using a steady-state visually evoked potential based brain-computer interface (BCI) for selection tasks in a computer game. In an experiment participants evaluated a BCI control and a comparable automatic speech recogniser (ASR) control in terms of workload, usability and engagement. The results showed that although BCI was a satisfactory modality in completing selection tasks, its use in our game was not engaging for the player. In our particular setup, ASR control appeared to be a better alternative to BCI control.