University of Pittsburgh, USA.
J Am Acad Child Adolesc Psychiatry. 2010 Feb;49(2):162-72.e1-5. doi: 10.1097/00004583-201002000-00010.
Changes in reward-related behavior are an important component of normal adolescent affective development. Understanding the neural underpinnings of these normative changes creates a foundation for investigating adolescence as a period of vulnerability to affective disorders, substance use disorders, and health problems. Studies of reward-related brain function have revealed conflicting findings regarding developmental change in the reactivity of the striatum and medial prefrontal cortex (mPFC) and have not considered puberty. The current study focused on puberty-specific changes in brain function and their association with mood.
A sample of 77 healthy adolescents (26 pre-/early pubertal, 51 mid-/late pubertal) recruited in a narrow age range (mean = 11.94 years, SD = 0.75) were assessed for sexual maturation and circulating testosterone, completed a functional magnetic resonance imaging (fMRI) guessing task with monetary reward, and underwent experience sampling of mood in natural environments. For comparison, 19 healthy adults completed the fMRI assessment.
Adolescents with more advanced pubertal maturation exhibited less striatal and more mPFC reactivity during reward outcome than similarly aged adolescents with less advanced maturation. Testosterone was positively correlated with striatal reactivity in boys during reward anticipation and negatively correlated with striatal reactivity in girls and boys during reward outcome. Striatal reactivity was positively correlated with real-world subjective positive affect and negatively correlated with depressive symptoms. mPFC reactivity was positively correlated with depressive symptoms.
Reward-related brain function changes with puberty and is associated with adolescents' positive affect and depressive symptoms. Increased reward-seeking behavior at this developmental point could serve to compensate for these changes.
奖励相关行为的变化是青少年情感发展的重要组成部分。了解这些正常变化的神经基础，为研究青少年时期易患情感障碍、物质使用障碍和健康问题的时期奠定了基础。奖励相关大脑功能的研究表明，纹状体和内侧前额叶皮层（mPFC）的反应性在发育过程中存在相互矛盾的发现，并且没有考虑到青春期。本研究主要关注青春期大脑功能的特定变化及其与情绪的关系。
本研究招募了 77 名健康青少年（26 名青春期前/早期，51 名青春期中期/晚期），年龄范围较窄（平均年龄为 11.94 岁，标准差为 0.75 岁），评估其性成熟度和循环睾酮水平，完成了一项带有金钱奖励的功能性磁共振成像（fMRI）猜测任务，并在自然环境中进行了情绪的经验采样。为了进行比较，19 名健康成年人完成了 fMRI 评估。
青春期成熟度较高的青少年在奖励结果期间表现出比成熟度较低的同龄青少年更少的纹状体反应和更多的 mPFC 反应。在奖励预期期间，男孩的睾酮与纹状体反应呈正相关，而在奖励结果期间，女孩和男孩的睾酮与纹状体反应呈负相关。纹状体反应与现实世界中的主观积极情绪呈正相关，与抑郁症状呈负相关。mPFC 反应与抑郁症状呈正相关。
奖励相关大脑功能随青春期而变化，并与青少年的积极情绪和抑郁症状相关。在这一发展阶段，增加的奖励寻求行为可能有助于弥补这些变化。
