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The First Commercial Brain–Computer<br />

Interface Environment<br />

Christoph Guger and Günter Edlinger<br />

1 Introduction<br />

The first commercial brain–computer interface environment has been developed so<br />

research centers could easily and quickly run BCI experiments to test algorithms<br />

and different strategies. A first BCI system was available on the market in 1999,<br />

and was continuously improved to the system available today, which is now used in<br />

more than 60 countries worldwide.<br />

Many factors influence the design <strong>of</strong> a BCI system, as shown in Fig. 1. There are<br />

technical issues and issues concerning the individual subject that must be addressed.<br />

Different brain signals are used in BCIs, such as the Electroencephalogram (EEG)<br />

recorded non-invasively from the scalp, or the Electrocorticogram (ECoG), which<br />

requires invasive electrodes. Therefore, different safety issues, sampling frequencies<br />

and electrode types are required. The applied signal processing algorithms<br />

have to work in on-line mode to provide real-time capabilities and decision making<br />

in real life situations. However, the algorithms must also work in <strong>of</strong>f-line mode<br />

to support in depth analysis <strong>of</strong> already acquired EEG data. The signal acquisition<br />

and processing unit has to ensure high data quality using e.g. over-sampling techniques<br />

providing a high signal to noise ratio (SNR). One type <strong>of</strong> BCI approach is<br />

based on motor imagery [1] (see also Chapters “Brain Signals for Brain–Computer<br />

<strong>Interfaces</strong>” and “Dynamics <strong>of</strong> Sensorimotor Oscillations in a Motor Task” in this<br />

book). This approach can be realized with only a few electrodes over the sensorimotor<br />

cortex. Some other approaches that use spatial filtering techniques [2] use about<br />

16–128 electrodes. A BCI based on ECoG signals also requires many channels (64–<br />

128) because dense electrode grids overlaying parts <strong>of</strong> the cortex [3] are utilized.<br />

C. Guger (B)<br />

Guger Technologies OG/g.tec medical engineering GmbH, Herbersteinstrasse 60, 8020 Graz,<br />

Austria<br />

e-mail: guger@gtec.at<br />

B. Graimann et al. (eds.), Brain–Computer <strong>Interfaces</strong>, The Frontiers Collection,<br />

DOI 10.1007/978-3-642-02091-9_16, C○ Springer-Verlag Berlin Heidelberg 2010<br />

281

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