Joseph Jane E, Zhu Xun, Lynam Donald, Kelly Thomas H
Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, SC 29425-0616, USA.
Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, SC 29425-0616, USA.
Neuroimage. 2016 Apr 1;129:40-54. doi: 10.1016/j.neuroimage.2015.12.005. Epub 2015 Dec 12.
Adolescence is a particularly vulnerable period for the onset of substance use disorders and other psychopathology. Individual variability in motivational tendencies and temperament and significant changes in functional brain organization during adolescence are important factors to consider in the development of substance use and dependence. Recent conceptualizations suggest that sensitivity to reward is heightened in adolescence and that this motivation tendency may precipitate subsequent substance abuse. The present study examined the role of personality traits in mesolimbic neurobehavioral response on a monetary incentive delay (MID) task in young adolescents (11-14 years) and emerging adults (18-25 years) using functional magnetic resonance imaging. As a group, adolescents were not more sensitive to gains than losses compared to adults during either anticipatory and feedback phases; instead, compared to adults they showed less sensitivity to incentive magnitude in mesolimbic circuitry during anticipation and feedback stages. However, personality modulated this response such that adolescents high in impulsivity or low in avoidance tendencies showed greater gain sensitivity and adolescents high in avoidance showed greater loss sensitivity during cue anticipation. In adults, mesolimbic response was modulated by the impulsivity construct such that high-impulsive adults showed reduced magnitude sensitivity during both anticipation and feedback compared to low impulsive adults. The present findings suggest that impulsive personality significantly modulates mesolimbic reward response during both adolescence and adulthood but avoidance and approach tendencies also modulate this response in adolescents. Moreover, personality modulated incentive valence in adolescents but incentive magnitude in adults. Collectively, these findings suggest that mesolimbic reward circuitry function is modulated by somewhat different parameters in adolescence than in adulthood.
青春期是物质使用障碍和其他精神病理学发病的一个特别脆弱的时期。青春期动机倾向和气质的个体差异以及功能性脑组织结构的显著变化是物质使用和依赖发展中需要考虑的重要因素。最近的概念化研究表明，青春期对奖励的敏感度会提高，这种动机倾向可能会引发随后的物质滥用。本研究使用功能磁共振成像，考察了人格特质在青少年（11 - 14岁）和青年成人（18 - 25岁）的金钱激励延迟（MID）任务中对中脑边缘神经行为反应的作用。作为一个群体，在预期和反馈阶段，青少年与成年人相比，对收益并不比对损失更敏感；相反，与成年人相比，他们在预期和反馈阶段中脑边缘回路对激励强度的敏感度较低。然而，人格调节了这种反应，使得在提示预期期间，冲动性高或回避倾向低的青少年表现出更高的收益敏感度，而回避倾向高的青少年表现出更高的损失敏感度。在成年人中，中脑边缘反应受冲动性结构的调节，与低冲动性成年人相比，高冲动性成年人在预期和反馈期间的强度敏感度都降低。目前的研究结果表明，冲动性人格在青春期和成年期都会显著调节中脑边缘奖励反应，但回避和趋近倾向也会在青少年中调节这种反应。此外，人格在青少年中调节激励效价，而在成年人中调节激励强度。总的来说，这些发现表明，青春期中脑边缘奖励回路的功能受与成年期略有不同的参数调节。
