演題詳細
Poster
ブレイン・マシン／コンピュータ・インターフェイス
BMI/BCI
| 開催日 | 2014/9/12 |
|---|---|
| 時間 | 11:00 - 12:00 |
| 会場 | Poster / Exhibition（Event Hall B） |
広帯域SSVEP-BMIに基づく環境制御システム開発
A development of an environmental control system based on wideband SSVEP-BMI
- P2-369
- 小松 知章 / Tomoaki Komatsu:1 高野 弘二 / Kouji Takano:1 神作 憲司 / Kenji Kansaku:1,2
- 1:国リハ研・脳機能部・脳神経 / Sys Neurosci Sect, Dept of Rehab for Brain Func, Res Inst of NRCD, Tokorozawa, Japan 2:電通大・脳科学 / Univ of Electro-Communications, Chofu, Japan
The P300-speller (Farewell and Donchin, 1988) is one of main methods in brain-machine interface (BMI) or brain-computer interface (BCI). We have developed a P300-BMI for environmental control; e.g., home electronic devices and information equipment (Takano et al., 2009; Kansaku, 2011), and reported successful operation of the system in patients with amyotrophic lateral sclerosis (ALS) (Ikegami et al., 2014). The steady-state visual evoked potentials (SSVEP) (Middendorf et al., 2000) is another main method in BMI, and we developed an SSVEP-BMI, which used high-frequency visual stimuli above the critical flicker frequency (CFF) (Sakurada et al., 2013). In this study, we developed an environmental control system, in which both P300 and wideband SSVEP are available. In the wideband SSVEP, we prepared visible (below CFF) and invisible (above CFF) flickering stimuli.
The environmental control system consisted of an 11.6 inch tablet PC with Windows 8, a bluetooth EEG amplifier, LED cubes that can provide 1 to 100 Hz flicker, I/O box, and non-adhesive solid-gel electrodes (Toyama et al., 2012). We introduced a multi-process architecture to the system, and each process coordinates via TCP sockets and JSON messages. Since the system was written in highly-portable C++, dominant part can also be processed on Windows 7, Windows 8 and OS X. The system reduced a CPU-load under 20% in the tablet PC through this study.
Two patients in ALS, a 63-year-old male in a hospital and a 48-year-old male at home, were asked to operate the SSVEP-BMI for environmental control. The experiments were conducted at least once per week for 1 month. We used three electrodes at Oz, AFz, and Fpz. We assessed visibly (25-45 Hz) vs. invisibly (52-65 Hz) flickering stimuli in the SSVEP-BMI. The system triggered a call button and a TV switch. The mean accuracy was 88.0% for the patient in the hospital, and 73.1% for the patient at home. These accuracies were sufficient for practical use (> 70%).
These suggest that our system is useful for practical application in patients with ALS.