Preferring fair resource distribution reflects human cooperative nature, but its neural correlates in young children are not well known. We investigated the neural mechanism of egalitarian resource sharing in five-to six-year-old children to examine the possibility that early egalitarianism requires behavioral control to inhibit selfish impulses. In Study 1, children participated in a behavioral control task in which they either needed or did not need to inhibit their impulsive behavioral responses in order to quickly press a key. They subsequently allocated their resources to strangers by choosing a 2:2, 3:1, or 4:0 distribution. The activation of the dorsolateral prefrontal (dlpfc) regions was recorded by functional near-infrared spectroscopy measurements. We found that dlpfc regions were activated during cognitive tasks involving behavioral control and also during the equal, but not the more selfish, allocations. There was no difference among these allocations. The results did not show evidence of an ego depletion effect on children's sharing behavior, which predicts that children will share less after their behavioral control is taxed in a cognitive task (i.e., their self-control resource depleted). Study 2 showed no activation of the dlpfc regions during third-party equal allocations in which there was no conflict between fairness and self-interest in the distribution of resources. Overall, we showed that costly equal sharing in young children relates to the activation of dlpfc regions. These results suggest that costly equal allocation has a common neural basis with behavioral control in five-to six-year-old children, implying that early egalitarian sharing requires dealing with conflicts between maximizing self-interest and following moral norms.

偏爱公平的资源分配反映了人类的合作性质，但其与幼儿的神经相关性尚不为人所知。我们调查了五到六岁儿童中平等资源共享的神经机制，以检验早期平等主义需要行为控制来抑制自私冲动的可能性。在研究1中，孩子参加了行为控制任务，其中他们需要或不需要抑制他们的冲动行为反应来快速按下按键。随后，他们通过选择2：2、3：1或4：0分配来将资源分配给陌生人。通过功能近红外光谱测量记录背外侧前额叶（dlpfc）区域的激活。我们发现dlpfc区域在涉及行为控制的认知任务中被激活，并且在相等但不是更自私的分配过程中被激活。这些分配之间没有差异。结果没有显示出自我耗竭对儿童分享行为的影响，这预示着在认知任务中对儿童的行为控制加重后（即，他们的自我控制资源被耗尽），儿童的分享将会减少。研究2表明，在第三方平等分配过程中dlpfc区域没有被激活，在公平分配和自利之间资源分配之间没有冲突。总体而言，我们表明，代价昂贵的幼儿平均分配与dlpfc区域的激活有关。这些结果表明，昂贵的均等分配在5至6岁的儿童中具有行为控制的共同神经基础，这意味着早期的平等分享需要解决在最大化自我利益和遵循道德规范之间的冲突。