Article Figures & Data
Figures
- Figure 1.
Experimental design. Subjects received 1 Hz rTMS during 15 min (b). The positioning of the coil over the left or right DLPFC was confirmed for all subjects using a three-dimensional MRI sequence with vitamin E capsule in place (sample shows right DLPFC). Four trials of the Risk Task are shown in d. Subjects performed all 100 trials in ∼7 min. The ratio of pink and blue boxes changed from trial to trial, and this is referred to in the text as level of risk. The numbers inside the bottom two boxes depict the reward/punishment sizes associated with the respective colors, in the text referred to as balance of reward. Reward associated with either choice of box color was fixed (10 vs 90, 20 vs 80, 30 vs 70, and 40 vs 60); the larger reward (and penalty) was associated with choice of the high-risk prospect, whereas the smallest reward (and penalty) was associated with the choice of the low-risk prospect, providing inherent reward conflict typical of risk-taking situations. The subject's task was to select one of these boxes to indicate the color of the box thought to hide a winning token (not shown in the samples). Subjects had to rate their mood before (a) and immediately after (c) the rTMS train.
- Figure 2.
a, Total points earned in 100 trials (means ± SEM). One-way ANOVA revealed a significant main effect of group (F(2,24) = 5.60; p = 0.011). Subjects stimulated over the right DLPFC earned significantly fewer points than those who received sham (p = 0.040) or the left DLPFC who received real rTMS (p = 0.020). b, Percentage choice of the low-risk prospect (means ± SEM) for all three groups. Repeated-measures ANOVA of subject group × level of risk × balance of reward revealed a main effect of group (F(2,24) = 4.92; p = 0.016), and post hoc analysis demonstrated that subjects who received rTMS over the right DLPFC were more likely to choose the high-risk prospect than those stimulated over the left DLPFC (p = 0.034) or those who received sham rTMS (p = 0.048). Indeed, seven of nine subjects who received right DLPFC rTMS ultimately performed among the subjects more prone to risk-taking, whereas most of those who received left DLPFC rTMS ended up in the group of subjects who were less inclined toward risk-taking. c, Percentage choice of the low-risk prospect (means ± SEM) as a function of the balance of reward. Repeated-measures ANOVA of subject group × level of risk × balance of reward revealed a main effect of balance of reward (F(3,72) = 17.19; p < 0.001). No interaction between group and balance of reward was found (F(6,72) = 1.03; p = 0.414).
Additional Files
Supplemental data
Files in this Data Supplement:
- supplemental material - Figure 1
- supplemental material - Figure 2
