OBJECTIVE: The white/gray flicker matrix has been used as a visual stimulus for the so-called P300 brain-computer interface (BCI), but the white/gray flash stimuli might induce discomfort. In this study, we investigated the effectiveness of green/blue flicker matrices as visual stimuli. METHODS: Ten able-bodied, non-trained subjects performed Alphabet Spelling (Japanese Alphabet: Hiragana) using an 8 x 10 matrix with three types of intensification/rest flicker combinations (L, luminance; C, chromatic; LC, luminance and chromatic); both online and offline performances were evaluated. RESULTS: The accuracy rate under the online LC condition was 80.6%. Offline analysis showed that the LC condition was associated with significantly higher accuracy than was the L or C condition (Tukey-Kramer, p < 0.05). No significant difference was observed between L and C conditions. CONCLUSIONS: The LC condition, which used the green/blue flicker matrix was associated with better performances in the P300 BCI. SIGNIFICANCE: The green/blue chromatic flicker matrix can be an efficient tool for practical BCI application.
OBJECTIVE: The white/gray flicker matrix has been used as a visual stimulus for the so-called P300 brain-computer interface (BCI), but the white/gray flash stimuli might induce discomfort. In this study, we investigated the effectiveness of green/blue flicker matrices as visual stimuli. METHODS: Ten able-bodied, non-trained subjects performed Alphabet Spelling (Japanese Alphabet: Hiragana) using an 8 x 10 matrix with three types of intensification/rest flicker combinations (L, luminance; C, chromatic; LC, luminance and chromatic); both online and offline performances were evaluated. RESULTS: The accuracy rate under the online LC condition was 80.6%. Offline analysis showed that the LC condition was associated with significantly higher accuracy than was the L or C condition (Tukey-Kramer, p < 0.05). No significant difference was observed between L and C conditions. CONCLUSIONS: The LC condition, which used the green/blue flicker matrix was associated with better performances in the P300 BCI. SIGNIFICANCE: The green/blue chromatic flicker matrix can be an efficient tool for practical BCI application.
Authors: G Townsend; B K LaPallo; C B Boulay; D J Krusienski; G E Frye; C K Hauser; N E Schwartz; T M Vaughan; J R Wolpaw; E W Sellers Journal: Clin Neurophysiol Date: 2010-03-26 Impact factor: 3.708
Authors: Chandra S Throckmorton; Kenneth A Colwell; David B Ryan; Eric W Sellers; Leslie M Collins Journal: IEEE Trans Neural Syst Rehabil Eng Date: 2013-03-21 Impact factor: 3.802