Targeting an efficient target-to-target interval for P300 speller brain–computer interfaces
- 405 Downloads
Longer target-to-target intervals (TTI) produce greater P300 event-related potential amplitude, which can increase brain–computer interface (BCI) classification accuracy and decrease the number of flashes needed for accurate character classification. However, longer TTIs requires more time for each trial, which will decrease the information transfer rate of BCI. In this paper, a P300 BCI using a 7 × 12 matrix explored new flash patterns (16-, 18- and 21-flash pattern) with different TTIs to assess the effects of TTI on P300 BCI performance. The new flash patterns were designed to minimize TTI, decrease repetition blindness, and examine the temporal relationship between each flash of a given stimulus by placing a minimum of one (16-flash pattern), two (18-flash pattern), or three (21-flash pattern) non-target flashes between each target flashes. Online results showed that the 16-flash pattern yielded the lowest classification accuracy among the three patterns. The results also showed that the 18-flash pattern provides a significantly higher information transfer rate (ITR) than the 21-flash pattern; both patterns provide high ITR and high accuracy for all subjects.
KeywordsBrain–computer interface Target to target interval P300 Flash pattern
- 1.Allison BZ, Neuper C (2010) Could anyone use a BCI? (B + H)CI: the human in brain-computer interfaces and the brain in human–computer interaction, Springer. pp 35–54Google Scholar
- 6.Dal Seno, Matteucci M, Mainardil L (2010) Online detection of P300 and error potentials in a BCI speller. Comput Intell Neurosci 307254Google Scholar
- 11.Hill J, Farquhar J, Martens S, Bießmann F, Schölkopf B (2008) Effects of stimulus type and of error-correcting code design on bci speller performance: NIPS [on line]. http://books.nips.cc/papers/files/nips21/NIPS2008_0359.pdf
- 31.Salvaris M, Sepulveda F (2009) Perceptual Errors in the Farwell and Donchin Matrix Speller. 4th international conference IEEE/EMBS Antalya, April, 275–78Google Scholar