Blest-Hopley Grace, Colizzi Marco, Giampietro Vincent, Bhattacharyya Sagnik
Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, United Kingdom.
Section of Psychiatry, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy.
Front Psychiatry. 2020 Aug 26;11:859. doi: 10.3389/fpsyt.2020.00859. eCollection 2020.
Cannabis use during the critical neurodevelopmental period of adolescence, may lead to brain structural, functional, and histological alterations that may underpin some of the longer-term behavioral and psychological harms associated with it. The endocannabinoid system performs a key regulatory and homeostatic role, that undergoes developmental changes during adolescence making it potentially more susceptible to the effects of exposure to cannabis during adolescence. Here, we synthesize evidence from human studies of adolescent cannabis users showing alterations in cognitive performance as well as in brain structure and function with relevant preclinical evidence to summarize the current state of knowledge. We also focus on the limited evidence that speaks to the hypothesis that cannabis use during adolescence, may pose a greater risk than use during adulthood, identify gaps in current evidence and suggest directions for new research. Existing literature is consistent with the association of cannabis use during adolescence and neurological changes. Adolescence cannabis users show altered functional connectivity within known functional circuits, that may underlie inefficient recruitment of brain regions, as largely increased functional activation has been observed compared to controls. This disruption in some cases may contribute to the development of adverse mental health conditions; increasing the chances or accelerating the onset, of their development. Preclinical evidence, further supports disruption from cannabis use being specific to the developmental period. Future studies are required to better investigate adolescent cannabis use with more accuracy using better defined groups or longitudinal studies and examine the permanency of these changes following caseation of use. Furthermore, research is required to identify heritable risk factors to cannabis use. There is a need for caution when considering the therapeutic potential of cannabis for adolescence and particularly in public discourse leading to potential trivialization of possible harm from cannabis use in adolescence. Current evidence indicates that adolescence is a sensitive period during which cannabis use may result in adverse neurocognitive effects that appear to show a level of permanency into adulthood.
在青春期这个关键的神经发育阶段使用大麻，可能会导致大脑结构、功能和组织学改变，这些改变可能是与大麻使用相关的一些长期行为和心理危害的基础。内源性大麻素系统发挥着关键的调节和稳态作用，在青春期会经历发育变化，这使得它在青春期可能更容易受到大麻暴露的影响。在这里，我们综合了来自对青少年大麻使用者的人体研究的证据，这些证据表明认知表现以及大脑结构和功能发生了改变，并结合相关临床前证据来总结当前的知识状态。我们还关注了有限的证据，这些证据支持这样一种假设，即青春期使用大麻可能比成年期使用带来更大的风险，识别当前证据中的差距，并提出新的研究方向。现有文献与青春期使用大麻和神经学变化之间的关联是一致的。青春期大麻使用者在已知的功能回路中表现出功能连接改变，这可能是大脑区域募集效率低下的基础，因为与对照组相比，观察到功能激活大幅增加。在某些情况下，这种破坏可能会导致不良心理健康状况的发展；增加其发展的可能性或加速其发病。临床前证据进一步支持大麻使用造成的破坏特定于发育时期。未来的研究需要使用定义更明确的群体或纵向研究，更准确地更好地调查青少年大麻使用情况，并在停止使用后检查这些变化的持久性。此外，需要进行研究以确定大麻使用的遗传风险因素。在考虑大麻对青少年的治疗潜力时，尤其是在可能导致对青春期大麻使用可能造成的危害进行潜在淡化的公共讨论中，需要谨慎。目前的证据表明，青春期是一个敏感时期，在此期间使用大麻可能会导致不良的神经认知影响，这些影响在成年期似乎会表现出一定程度的持久性。
