Table 3.

Accuracy (% correct trials), number of correct responses (safe condition: out of 60 trials; threat condition: out of 54 trials), and reaction times (in milliseconds) for N-back performance for participants who were administered placebo (N = 27) and methylphenidate (N = 26). Standard deviations are in parentheses

Condition	Placebo				Methylphenidate
	Safe 1-back	Safe 3-back	Threat 1-back	Threat 3-back	Safe 1-back	Safe 3-back	Threat 1-back	Threat 3-back
Accuracy	93.3 ± (6.7)	73.5 ± (9.2)	93.7 ± (7.9)	73.4 ± (9.2)	95.1 ± (7.7)	72.6 ± (9.9)	93.2 ± (5.6)	75.4 ± (10.5)
No. of correct trials	55.98 ± (4.0)	44.1 ± (5.5)	50.60 ± (4.3)	39.64 ± (5.0)	57.06 ± (4.6)	43.56 ± (5.9)	50.38 ± (3.0)	40.72 ± (5.7)
Reaction times	741 ± (112)	923 ± (260)	731 ± (116)	930 ± (225)	707 ± (176)	895 ± (285)	725 ± (182)	912 ± (303)