Gaming
Although gaming has not been the main focus of BCI research, there exist some prototypes that demonstrate the feasibility of games controlled by a BCI (Millán, 2003; Lalor et al., 2005; Krepki et al., 2007; Nijholt et al., 2008b; Tangermann et al., 2008; Finke et al., 2009; Nijholt, 2009). Such BCI games could allow severely disabled persons to not only experience a little bit of entertainment, but to also to improve their quality of life, mainly through social interaction. For instance, Tangermann et al. (2008) shows evidence that real-time BCI control of a physical game machine is possible with little subject training. The gaming machine studied (a standard pinball machine) required only two classes for control with fast and precise reaction; predictive behavior and learning are mandatory. Games can be either competitive (requiring fast responses) or strategic (usually slower).
These BCI games are based on different BCI protocols, from spontaneous EEG (Millán, 2003; Krepki et al., 2007; Tangermann et al., 2008) to evoked EEG potentials (Lalor et al., 2005; Finke et al., 2009), where the user delivers (as usual for a BCI) mental commands to control some aspect of the game. Another alternative is to determine the user's mental or affective state from their EEG and to use this information to adapt the dynamics of the game to the user's affective state (Nijholt et al., 2008b). As stated in Nijholt et al. (2008a), “Measuring brain activity for gamers can be used so that the game environment (1) knows what a subject experiences and can adapt game and interface in order to keep the gamer “in the flow” of the game, and (2) allows the gamer to add brain control commands to the already available control commands for the game.” This perspective matches well that described in Williamson (2006) when discussing a general framework for interaction design.
It is usually assumed that, because of the huge yearly turnovers of the game industry, once BCI games reach the mass market, BCI technology would become so cheap that every disabled person would be able to afford it for functional interaction. Some support this view. For instance, commercial “BCI” sensors are coming into the mainstream gaming world (e.g., Emotiv and Neurosky). Also, as Nijholt (2009) points out: “There are also other reasons that make games, gamers and the game industry interesting. Gamers are early adaptors. They are quite happy to play with technology, to accept that strong efforts have to be made in order to get minimal advantage, and they are used to the fact that games have to be mastered by training, allowing them to go from one level to the next level and to get a higher ranking than their competitors”. However, we cannot take for granted that the kind of BCI technology (sensors and brain signals) that the game industry would eventually develop will automatically be appropriate for functional interaction. This is the case for current “BCI” game sensors that are limited in number and position over the users head (normally just over the forefront, where there is no hair).
One concern with the mass-produced BCI games is proper evaluation; namely, how to prove that the user's brainwaves are the actual control signals driving the game. Of course, from a hybrid BCI perspective, gamers can (and must) also use other physiological signals and interaction modalities. The point, however, is to demonstrate that users have a sufficient degree of mental control for those aspects of the game that require so, as advertised. This issue also raises the question of how to evaluate games as a whole to ensure that they provide a valuable and enjoyable experience. In this respect, the Fun of Gaming (FUGA) project advocates a multi-dimensional evaluation using self-reports, behavioral observations and psychophysiological measures as each in itself is insufficient to get the full picture (IJsselsteijn et al., 2008). Much of the research in pleasure and satisfaction in entertainment focuses on gaming but some might be applied to entertainment in general. For example, “fun” in a game includes challenge, curiosity, fantasy, and Csikszentmihalyi's theory of flow (level of engagement that one is completely absorbed in the current activity and enjoys it in itself without any need for future benefit), but these can also apply to interactive art and creativity (and by extension interactive media, Costello and Edmonds, 2007). Only such a kind of evaluation will prove beneficial for BCI games in general, and for disabled people in particular. Otherwise, BCI games will be just another “fast-food toy” that customers buy and stop using quickly, thus risking to seriously damage the credibility of the BCI field – such a blow that early in its development stage could cripple the field, by projecting a negative image to the public, other industrial sectors, and to funding agencies.