Table 2. n-back task performance for target stimuli by genotype groups.

Values are reported as mean ± standard error of the mean. Reported p-values reflect COMT × DARPP-32 interaction effects in a 3 (COMT genotype group) × 2 (DARPP-32 genotype group) ANOVA with white ethnicity and sex included as covariates. Conventions as for Table 1.

	COMT Val/Val D-32 C (n = 15)	COMT Val/Met D-32 C (n = 20)	COMT Met/Met D-32 C (n = 9)	COMT Val/Val D-32 T/T (n=14)	COMT Val/Met D-32T/T (n=23)	COMT Met/Met D-32 T/T (n =16)
Target Accuracy (%)
0-back	92.9 ± 2.0	90.7 ± 1.6	85.2 ± 2.4	92.9 ± 2.0	89.6 ± 1.5	92.9 ± 1.8
2-back	88.8 ± 4.2	86.0 ± 3.5	70.9 ± 5.2	82.4 ± 4.3	81.4 ± 3.3	77.2 ± 3.9
3-back	66.0 ± 4.1	69.0 ± 3.5	62.5 ± 5.1	70.2 ± 4.1	61.7 ± 3.2	66.5 ± 3.8
Target Correct RT (ms)
0-back	481.1 ± 18.1	497.5 ± 15.2	507.8 ± 22.4	516.1 ± 18.3	494.8 ± 14.2	537.5 ± 16.9
2-back	690.1 ± 32.1	685.0 ± 27.0	724.4 ± 39.6	710.9 ± 32.4	699.1 ± 25.2	707.6 ± 29.9
3-back	729.0 ± 33.6	758.5 ± 28.3	724.2± 41.5	771.8 ± 33.9	726.2 ± 26.4	793.3 ± 31.4

RT, reaction time.