Table 2.

Accuracy and reaction times (Mean ± SD) for the spatial n-back tasks.

		Total (n = 18)	Low performers (n = 9)	High performers (n = 9)
Hits (%)	0-back	95.8 ± 8.0	96.7 ± 6.0	94.8 ± 9.9
	1-back	91.2 ± 12.0	89.5 ± 13.4	92.8 ± 10.9
	2-back	84.0 ± 12.9	78.4 ± 11.8	89.5 ± 12.0
Correct rejections (%)	0-back	99.2 ± 2.0	99.2 ± 2.3	99.2 ± 1.6
	1-back	97.5 ± 2.5	97.2 ± 2.3	97.9 ± 2.7
	2-back	89.9 ± 9.0	88.1 ± 9.3	91.7 ± 8.8
RT target (ms)	0-back	665.9 ± 110.0	697.7 ± 104.3	634.0 ± 112.0
	1-back*	772.7 ± 148.2	842.3 ± 138.8	703.1 ± 128.4
	2-back**	1048.5 ± 333.8	1316.4 ± 229.2	780.7 ± 151.0
RT non-target (ms)	0-back	643.8 ± 87.0	665.9 ± 73.3	621.7 ± 98.0
	1-back	743.0 ± 124.6	761.2 ± 77.1	724.8 ± 162.1
	2-back**	958.5 ± 270.7	1143.4 ± 221.5	773.6 ± 172.3
Composite score	0-back	14.6 ± 2.0	14.1 ± 1.9	15.2 ± 2.1
	1-back*	12.2 ± 2.7	11.0 ± 2.8	13.4 ± 2.0
	2-back**	8.9 ± 3.3	6.2 ± 1.4	11.7 ± 2.0

**p ≤ 0.005, *p < 0.05 low performers vs. high performers.