Figure 1.

The effect of the catechol-O-methyltransferase (COMT) valine¹⁵⁸methionine (Val¹⁵⁸Met) and dopamine transporter (DAT1)3′ variable number of tandem repeats (VNTR) polymorphisms on Freeze-Frame performance. Error bars indicate the 95% confidence interval of the mean. (a) The mean proportion of looks to the distractors in the boring and interesting Freeze-Frame trials in the three COMT Val¹⁵⁸Met genotype groups in the Caucasian subsample (Met/Met, n = 19; Val/Met, n = 37; Val/Val, n = 23). An asterisk indicates a significant difference from the Met/Met group at p < .01. (b) The mean proportion of looks to the distractors in the boring and interesting Freeze-Frame trials in the DAT1 3′ VNTR 10/10 and non-10/10 genotype groups (10/10, n = 60; non-10/10, n = 42); the overall difference between the two genotype groups (across trial types) was significant at p < .05. (c) The effect of the COMT Val¹⁵⁸Met polymorphism on the mean proportion of looks to the distractors in the interesting Freeze-Frame trials in the two DAT1 genotype groups (10/10 + Met/Met, n = 19; 10/10 + Val/Met, n = 26; 10/10 + Val/Val, n = 15; non-10/10 + Met/Met, n = 9; non-10/10 + Val/Met, n = 21; non-10/10 + Val/Val, n = 12). An asterisk indicates a significant difference from the Met/Met group at p < .01 within the non-10/10 group, and a triangle indicates a significant difference at p < .01 between the Val/Met group in the non-10/10 group compared with the Val/Met group in the 10/10 group.