A Survey of Stimulation Methods Used in SSVEP-Based BCIs

Table 1

Characteristics of light stimuli.

Frequency band	Study	Stimulus			Bit rate (bits/min)
		Device	Frequency (Hz)	Color
L	Maggi et al. 2006 [19]	LED	6, 7, 8, 10 Hz	Green	—
	Piccini et al. 2005 [20]	LED	6–10 Hz	—	—
M	Lüth et al. 2007 [21]	LED	13, 14, 15, 16, 17 Hz	Red	—
	Valbuena et al. 2007 [22]	LED	13, 14, 15, 16 Hz	—	—
	Leow et al. 2007 [23]	LED	14–29 Hz	Red	—
	Materka and Byczuk 2006 [24]	LED	25,  26.5625, 28.125, 29.6875 Hz	—	—
	Calhoun et al. 1996 [12]	Fluorescent light	13.25 Hz	—	—
H	Garcia Molina 2008 [25]	LED	40–50 Hz	White	—
	Huang et al. 2008 [17]	Xe-light	30–50 Hz	—	—
	Materka et al. 2007 [26]	LED	32–40 Hz	—	—
	Materka and Byczuk, 2006 [27]	LED	34–40 Hz	—	—
L+M	Parini et al. 2009 [3]	LED	6, 7, …, 17 Hz	Green	51.47
	Bin et al. 2008 [28]	LED	10, 11, 12, 13 Hz	—	—
	Wu and Yao 2008 [29]	LED	8.3, 10 Hz	White	—
	Wu et al. 2008 [9]	LED	4.6, 10.8, 16.1 Hz	White	—
	Müller-Putz et al. 2008 [30]	LED	6, 7, 8, 13 Hz	Red	—
	Müller-Putz and Pfurtschelle 2008 [31]	LED	6, 7, 8, 13 Hz	Red	—
	Scherer et al. 2007 [32]	LED	6.25,  7.25, 8.00, 13.00 Hz; 11.75, 13.00, 15.25, 17.25 Hz	Red	—
	Jia et al. 2007 [33]	LED	6,  6.5,  7,…, 19 Hz	—	46.1
	Friman et al. 2007 [34]	LED	5, 7, 9, 11, 13, 15 Hz	—	—
	Friman et al. 2007 [35]	LED	13, 14, 15, 16, 17 Hz	Red	27–30
	Müller-Putz et al. 2005 [36]	LED	6, 7, 8, 13 Hz	Red	31.5
	Wang et al. 2004 [37]	LED	9–17 Hz	—	42
	Gao et al. 2003 [15]	LED	6, 6.195, 6.390, …, 15	Green	68
M+H	Wang et al. 2005 [38]	LED	21,23,…,43 Hz	White	—
L+M+H	Ruen et al. 2007 [39]	LED	7–35 Hz	Red	—