Schreuder et al. Listen, you are writing! Nijboer et al., 2008b). The question if ERP paradigms are suited for late stage ALS patients still remains open. Recently an alternative auditory method was introduced, called PASS2D (Höhne et al., 2011), which is based on (Schreuder et al., 2010). Instead of using a free-ﬁeld setup, a headphone setup was tested using cues differing in two dimensions (tone and loca- tion). The PASS2D and AMUSE paradigm have similarly high performances, which are competitive with state-of-the-art visual, covert attention BCIs. They furthermore complement each other in several interesting aspects. A headphone setup is portable, small, and requires very little alteration to the home environ- ment. It may be better suited for mobile user. On the downside, headphones may lead to social exclusion as the user might have limited perception of environmental sounds. The AMUSE para- digm is less mobile and requires an initial mechanical setup to position the speakers around the user. However, no social exclu- sion occurs, as the user can perceive stimuli and environmental sound at the same time. As end-users might be relatively immo- bile, the choice between AMUSE and PASS2D depends on the user’s liking. In conclusion, the AMUSE paradigm complements the current visual BCI systems with a realistic and high performing alterna- tive. The majority of users can successfully control the system and concrete steps of improvement have been offered. Further- more, a method for dynamic trial stopping was introduced, which signiﬁcantly increased performance. ACKNOWLEDGMENTS The authors would like to thank Thomas Denck, David List and Larissa Queda for their help with performing the experi- ments. Furthermore, they thank Klaus-Robert Müller and Ben- jamin Blankertz for their fruitful discussions on the methodology. This work was partly supported by the European Information and Communication Technologies (ICT) Programme Project FP7- 224631 and 216886, by grants of the Deutsche Forschungsgemein- schaft (DFG; MU 987/3-2) and Bundesministerium fur Bildung und Forschung (BMBF; FKZ 01IB001A, 01GQ0850) and by the FP7-ICT Programme of the European Community, under the PASCAL2 Network of Excellence, ICT-216886. This publication only reﬂects the authors’ views. Funding agencies are not liable for any use that may be made of the information contained herein. SUPPLEMENTARY MATERIAL The Data Sheet 1 and Video 1 for this article can be found online at http://www.frontiersin.org/neuroprosthetics/10.3389/fnins.2011. 00112/abstract REFERENCES Acqualagna, L., Treder, M. S., Schreuder, M., and Blankertz, B. (2010). A novel brain-computer interface based on the rapid serial visual presentation paradigm. Conf. Proc. IEEE Eng. Med. Biol. Soc. 1, 2686–2689. Allison, B. Z., and Pineda, J. A. (2006). 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