美国研究人员16日说，大脑中一些基因会影响人们的策略性行为，包括赌博、投资等。
加州大学伯克利分校和伊利诺伊大学厄巴纳-尚佩恩分校研究人员在美国《国家科学院学报》上报告说，这些基因通过大脑中的神经递质多巴胺发挥作用。多巴胺是大脑奖赏系统的关键组成部分，与人的快感有关，而他们的研究则首次把人们的策略性行为与多巴胺调控基因联系起来。研究人员在新加坡招募了217名大学生，从其基因组中找到约70万个基因突变，新研究主要针对其中12个多巴胺调控基因的143个突变。然后，这些受试者被安排通过电脑与一名匿名对手进行赌博，研究人员在一旁利用磁共振成像技术监控他们的大脑活动。
研究表明，那些能更好地判断对手想法并予以回应的人，他们大脑内侧前额叶皮层中的3个多巴胺调控基因出现突变；那些在失败后能更好地改变应对策略的人，他们大脑纹状体的2个多巴胺调控基因出现突变。
这项研究把赌博、投资等策略性决定与一系列基因联系在一起。研究人员下一步计划在老年人群中展开研究，分析事业成就与基因等因素之间是否存在关联。
Neural representation of expected value in the adolescent brain
Previous work shows that the adolescent reward system is hyperactive, but this finding may be confounded by differences in how teens value money. To address this, we examined the neural ontogeny of objective value representation. Adolescent and adult participants performed a monetary gambling task in which they chose to accept or reject gambles of varying expected value. Increasing expected value had a stronger influence over gambling choices in adolescents relative to adults, an effect that was paralleled by greater activation in the ventral striatum in adolescents. This unique adolescent ventral striatum response remained even after matching groups on acceptance behavior. These behavioral and neural data suggest that the value of available options has a greater influence in adolescent versus adult choices, even when objective value and subjective choice are held constant. This research provides further evidence that hyperactivation of reward circuitry in adolescence may be a normative ontogenetic shift that is due to greater valuation in the adolescent brain.
