Figure 2
From: Manipulation of Pro-Sociality and Rule-Following with Non-invasive Brain Stimulation

Payoff consequences. All possible combinations of outcomes in the ‘me’ block and ‘other person’ block. Assuming that the rule was to put each ball in the orange box in the ‘rule’ block, the rule sometimes demanded to choose the positive option (green), a neutral option (yellow), or a negative option (red).