基因与同伴环境对青少年冒险行为的调控及其神经机制

Adolescence is a crucial developmental period over the life-span, often characterized with increased risk-taking behaviors that may jeopardize their optimal psychological and physical functioning. Revealing the risk factors of adolescent risk-taking behaviors and its neurophysiological mechanisms is not only a scientific problem that has been attracting scholars for many areas, but it is also a critical social issue that government is devoted to solve. The occurrence of teenager’s risk-taking behaviors are often accompanied with reward and emotional process. Some contemporary studies have investigated the neural basis and genes related to reward and emotional process in risk decisions, however, the role of environmental factors has been vastly overlooked.. Recent research has found that peer is an important environmental factor affecting adolescents’ risk-taking behaviors, probably through the interaction with related genes. To reveal this mechanism, this project plans to carry out two studies: (1) to explore gene polymorphism’s influence on the developmental trajectory of teenager’s risk taking behaviors and its mediating mechanisms through one-year longitudinal study; and (2) through a series of ERPs experiments, to reveal the dynamic process of interaction between gene polymorphism and peer environment in adolescents’ risk taking decisions. These results aid to reveal the neurophysiologic mechanisms of adolescents' risk taking behaviors, and also deepen our understandings of the elevated emergence of impulse behavior during adolescence, all of which provide new theoretical foundation for decreasing and preventing adolescents risk taking behaviors.

青春期不仅是个体毕生发展过程中非常关键的时期，也是冒险行为的高发时期。揭示青少年冒险行为的易感因素及其神经生理机制，不仅是众多领域学者关注的科学问题，更是国家当前需要关心和解决的重要社会问题。青少年冒险行为的发生往往伴随着奖赏与情绪加工，当前已有研究考察了风险决策中奖赏与情绪加工相关的神经基础和遗传基因，但忽略了对环境因素的考量。新近研究指出，同伴是青少年冒险行为的重要环境因素，可能与遗传因素交互影响青少年在风险决策中的冒险偏好。为揭示这一机制，本项目拟开展两项研究：(1) 通过为期1年的纵向追踪研究，探索基因多态性位点对青少年冒险行为发展轨迹的影响及其中介机制；(2) 通过系列ERPs实验，探究基因与同伴环境交互影响青少年冒险行为的动态过程。所得结果不仅可揭示青少年冒险行为的神经生理机制，还有助于我们更好地理解青少年高冲动行为的发生发展机制，为降低和预防青少年冒险行为提供新的理论依据。

冒险行为(risk-taking behaviors)是导致全球青少年意外死亡率上升的重要原因，对青少年健康发展造成极大威胁。为何青少年冒险水平高于儿童和成人？这不仅是发展心理学领域的一个重要科学问题，更是社会、学校和家庭关心的现实问题。青少年冒险行为的发生往往伴随着奖赏与情绪加工，以往研究考察了风险决策中奖赏与情绪加工相关的神经基础和遗传基因，但同伴环境与基因的交互效应较缺乏关注。同伴伴随青春期个体的成长和发展，是青少年冒险行为的重要环境因素，可能与遗传因素交互影响青少年在风险决策中的冒险偏好。本研究运用纵向追踪、行为实验、事件相关电位和基因技术结合的研究方法，探究同伴影响青少年冒险行为的认知神经机制。研究发现(1) 多巴胺基因的rs686，rs6267，rs27072，rs1800497，rs1800532等位点，五羟色胺的rs6313，rs16859448，rs1800532等位点均与青少年冒险行为密切相关；(2) 越轨同伴交往和同伴排斥均会促使青少年更偏爱冒险行为；(3) 行为激活系统在过度竞争与青少年冒险行为间的中介效应仅在COMT基因rs6267位点的GG型基因携带者中显著；自我控制在同伴排斥和青少年冒险行为间的中介效应仅在5-HTR2A五羟色胺基因rs6313位点的GG和GA基因型的青少年中显著。(4) 相比于竞争情境，单人情境下的青少年会更偏爱冒险选项。在反馈评估阶段，在单人情境下被试在收益/损失反馈后均诱发一个更大的P300成分，并观察到一个更小的FRN差异波。截至目前，本项目发表论文15篇，其中11篇发表在《Computers in Human Behavior》《Current Psychology》《Children and Youth Services Review》《心理科学》等SSCI/CSSCI权威期刊上。项目负责人和成员在全国心理学学术会议等重大会议上报告成果16人次，科普推文累计阅读量5万余次，培养硕士研究生14人，本科生38人。