Medical University of South Carolina, Department of Psychiatry and Behavioral Sciences, Charleston, SC, USA.
University of California, San Diego School of Medicine, Department of Psychiatry, La Jolla, CA, USA.
Addict Behav. 2019 Feb;89:20-28. doi: 10.1016/j.addbeh.2018.09.015. Epub 2018 Sep 11.
Adult and adolescent studies suggest increased motivational responses to cannabis cues among regular cannabis users. However, functional magnetic resonance imaging (fMRI) studies have not explored neural activation in response to visual cannabis cues among adolescents in the United States. Gaining a better understanding of the neural circuits related to cue-elicited craving during adolescence may shed light on the neural basis for the development of problematic cannabis use that could ultimately be targeted for interventions.
41 non-treatment-seeking youth (ages 17-21; mean age = 18.83; 46.3% female) who reported regular cannabis use underwent fMRI scanning involving a visual cannabis cue task and completed self-report and biological measures. Whole-brain activation was examined for cannabis cues compared to non-cannabis cues, and for active versus passive cannabis cues. Associations between self-reported substance use and task activation were examined.
Cannabis images were identifiable to adolescents and were rated as more rewarding than matched non-cannabis images (p < .05). Greater activation was found for the cannabis cues compared to non-cannabis cues in bilateral posterior cingulate, cuneus, fusiform, precuneus, inferior temporal and parahippocampal gyri, as well as left thalamus, medial frontal and superior frontal gyri. Cue-elicited activation was not significantly associated with self-reported cannabis use (ps > 0.05). No differences were observed for the active versus passive cue contrast.
Cannabis-using youth show more activation to cannabis cues than non-cannabis cues in brain regions underlying incentive salience, reward, and visual attention. This task could be useful for future studies examining neural underpinnings of reward processes in adolescent cannabis users.
成人和青少年研究表明,经常使用大麻的人对大麻线索的动机反应增强。然而,功能性磁共振成像(fMRI)研究尚未探索美国青少年对视觉大麻线索的神经激活。更好地了解与青春期线索诱发的渴望相关的神经回路,可能揭示出与问题性大麻使用发展相关的神经基础,最终可以针对这些基础进行干预。
41 名非治疗寻求的青少年(年龄 17-21 岁;平均年龄=18.83;46.3%为女性)报告经常使用大麻,他们接受了 fMRI 扫描,涉及视觉大麻线索任务,并完成了自我报告和生物测量。与非大麻线索相比,对大麻线索进行了全脑激活检查,并对主动与被动大麻线索进行了检查。检查了自我报告的物质使用与任务激活之间的关联。
大麻图像对青少年来说是可识别的,并且比匹配的非大麻图像被评为更有奖励性(p<0.05)。与非大麻线索相比,大麻线索在双侧后扣带回、楔前叶、梭状回、楔叶、下颞叶和海马旁回,以及左丘脑、内侧额回和额上回,激活程度更高。线索诱发的激活与自我报告的大麻使用没有显著相关性(p>0.05)。主动与被动线索对比没有观察到差异。
与非大麻线索相比,使用大麻的青少年对大麻线索的大脑区域表现出更强的激活,这些区域是激励显著性、奖励和视觉注意力的基础。这个任务对于未来研究青少年大麻使用者的奖励过程的神经基础可能很有用。