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(intendiX ) is a commercial brain-computer interface (BCI) environment. intendiX was introduced in 2009 by Guger Technologies OG, or (g.tec ), an Austrian company that manufactures BCI systems and components. intendiX is designed as a personal BCI that anyone can use without technical training or outside support. It is robust to many types of environmental noise and can operate in home or hospital environments. Most people can use intendiX to spell five to ten characters per minute within about ten minutes of training. While intendiX has been used as an assistive technology by persons with severe disabilities, performance may be worse among users with disabilities due to fatigue, visual deficits, or impaired concentration, attention, or memory. intendiX can rely on one of : P300 and SSVEP. Both of these are very well established paradigms in BCI research,〔Allison, B.Z., Faller, J., and Neuper, C. (2012). BCIs that Use Steady-State Visual Evoked Potentials or Slow Cortical Potentials. In: Brain-Computer Interfaces: Principles and Practice, editors: Wolpaw, J.R. and Wolpaw, E.W. Oxford University Press.〕 Research articles have shown that nearly all people with a healthy visual system can use these types of BCIs. Both of these approaches require the user to pay attention to a specific region of the monitor. In a P300 BCI, different items on the monitor (such as letters) flash while the user is instructed to silently count each time a target item flashes. The BCI can identify the target item by determining which flashes elicited brain signals reflecting attention to that item. One of the most distinct such signals is the P300, hence the name. BCIs that rely on steady state visual evoked potentials (SSVEPs) instead rely on items that flicker instead of flash. The user focuses on one of the flickering items, producing SSVEP activity at the same frequency as that item. SSVEP signals are often found at harmonics of the stimulation frequency as well, which most SSVEP BCIs (including intendiX) exploit to improve performance. Therefore, a BCI can determine the target item by identifying the peak frequencies in the user's visual areas, which can only correspond to one of the many items on the monitor. intendiX is an evolving product, with new components, options and upgrades each year. Like any BCI, the intendiX system requires four components: sensors that detect brain activity; signal processing algorithms that identify relevant brain signals in realtime; a device or application where the output signal is sent; and an operating environment that connects these components to each other and mediate interaction with the user. While these four components are presented somewhat differently, they are well recognized across review and commentary articles in the BCI community (Wolpaw et al., 2002;〔Wolpaw, J.R., Birbaumer, N., McFarland, D.J., Pfurtscheller, G., and Vaughan, T. M. (2002). Brain–computer interfaces for communication and control. Clinical Neurophysiology, 113(6), 767-791.〕 Allison et al., 2007,〔Allison, B.Z., Wolpaw, E.W., & Wolpaw, J.R. (2007). Brain computer interface systems: Progress and prospects. British review of medical devices, 4(4):463-474.〕 2012; Wolpaw and Wolpaw, 2012〔Wolpaw, J.R. and Wolpaw, E.W. (2012). Brain-Computer Interfaces: Something New Under the Sun. In: Brain-Computer Interfaces: Principles and Practice, editors: Wolpaw, J.R. and Wolpaw, E.W. Oxford University Press.〕). == intendiX components == Sensors: The first intendiX system, released in 2009, allowed users to work with either passive or active electrodes. While both of these electrodes require electrode gel, like conventional electrodes, the active electrodes do not require skin preparation and are more robust to external noise. This is because active electrodes feature amplifiers and other electronics within each electrode, whereas passive electrodes first send brain signals along cables before amplification. In 2010, g.tec introduced the Sahara dry electrode, which does not require gel. Signal processing: In typical BCIs, signal processing often involves different stages. For example, spatial filtering algorithms will determine how to best utilize information from the different electrodes, and pattern classification may categorize the resulting data. The intendiX system uses different signal processing algorithms for different types of brain signals. With P300 signals, intendiX relies on stepwise linear discriminant analysis (SWLDA), which is well established within the P300 BCI research community. The more general approach, LDA, is used in other types of BCIs as well.〔C. Guger, H. Ramoser, G. Pfurtscheller, Real-time analysis with subject-specific spatial patterns. IEEE Trans Rehabil Eng. 2000 Dec;8(4):447-56.〕 With SSVEP activity, intendiX instead relies on bandpower at different frequencies. A simple SSVEP BCI might present two stimuli on a monitor; the left stimulus oscillates at 8 Hz and the right at 13 Hz. If the user's visual areas show an increase at 8 Hz and its harmonics, a signal processing algorithm can identify this spike and thus infer that the user is focusing on the left stimulus. Device/Application: Initially, intendiX was used to control a speller. Using the extendiX system, users can also control any smart home device such as a television, music player, air conditioner, or light. extendiX can control other devices as well, such as mobile robots or games. extendiX receives commands from intendiX via UDP and could thereby control any external device. In March 2012, g.tec presented the pre-release of their new Screen Overlay Control Interface (SOCI) at the CeBIT exposition in Hannover, Germany. Visitors to the g.tec booth could use the intendiX system to play World of Warcraft and Angry Birds, and additional game interfaces are being developed. The SOCI will be publicly available later in 2012. Operating Environment: The intendiX system interacts with users in different ways, depending on whether it is a P300 or SSVEP BCI. Both approaches require paying attention to different regions of the monitor to produce distinct brain signals that the BCI can recognize. intendiX also includes software to determine when users are not paying attention based on their EEG signals. This way, the system can easily enter a "sleep" mode without any instruction from the user, and return to an active state when the user again begins paying attention to the activity on the monitor. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Intendix」の詳細全文を読む スポンサード リンク
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