Ethier-Gagnon Mikaela A, DeGrace Sarah, Romero-Sanchiz Pablo, Helmick Carl A, Tibbo Philip G, Crocker Candice E, Good Kimberly, Rudnick Abraham, Cosman Tessa, Barrett Sean P, Stewart Sherry H
From the Departments of Psychology and Neuroscience (Ethier-Gagnon, DeGrace, Romero-Sanchiz, Cosman, Barrett, Stewart), and Psychiatry (Ethier-Gagnon, DeGrace, Helmick, Tibbo, Crocker, Good, Rudnick, Cosman, Barrett, Stewart), and Diagnostic Radiology, Dalhousie University, Halifax, N.S. (Crocker); the School of Psychology, University of Sussex, Brighton, UK (Romero-Sanchiz).
From the Departments of Psychology and Neuroscience (Ethier-Gagnon, DeGrace, Romero-Sanchiz, Cosman, Barrett, Stewart), and Psychiatry (Ethier-Gagnon, DeGrace, Helmick, Tibbo, Crocker, Good, Rudnick, Cosman, Barrett, Stewart), and Diagnostic Radiology, Dalhousie University, Halifax, N.S. (Crocker); the School of Psychology, University of Sussex, Brighton, UK (Romero-Sanchiz)
J Psychiatry Neurosci. 2025 Aug 8;50(4):E237-E247. doi: 10.1503/jpn.250064. Print 2025 Jul-Aug.
A history of trauma increases risk for excessive and problematic cannabis use, and this relationship may involve conditioned cannabis craving to trauma cues arising through classical and operant conditioning. Alterations in functional connectivity (FC) after trauma reminders within or between brain regions associated with reward processing may potentiate this link; however, the underlying neural mechanisms remain unstudied.
We recruited cannabis users with trauma histories from February 2021 to August 2022. Participants completed a semi-structured interview about a personally relevant traumatic experience, a typical cannabis use situation unrelated to trauma or stress, and an emotionally neutral situation, with responses informing development of 3-minute audiovisual cues. Using a randomized cross-over design, we presented personalized audio recordings and images of the neutral, cannabis-related, and trauma-related situations to participants in counterbalanced order using a cue reactivity paradigm adapted for the magnetic resonance imaging (MRI) environment. Participants self-reported on subjective cannabis craving and positive and negative affect after each cue presentation. We measured FC between striatal, cortical, and limbic regions via functional MRI during each cue.
We included 27 cannabis users with trauma histories (74.1% female, average age 32.2 years, standard deviation 10.5 years). Trauma cues increased cannabis craving and negative affect and decreased positive affect relative to other cues. Cannabis cues increased craving relative to neutral and baseline cues. Trauma cues increased FC within the striatum and between striatal-cortical regions relative to neutral cues and increased striatocortical FC relative to cannabis cues. Cannabis cues increased cortical and corticolimbic FC relative to trauma cues and increased striatocortical FC relative to neutral cues.
The sample was small in size and not formed exclusively of participants with diagnoses of posttraumatic stress disorder or cannabis use disorder.
Findings suggested potential neural mechanisms underlying the link between trauma and cannabis use. Trauma- and cannabis-related cues may potentiate cannabis craving through altered reward circuit FC.
创伤史会增加过度使用大麻及出现大麻使用问题的风险，这种关系可能涉及通过经典条件作用和操作性条件作用对创伤线索产生的条件性大麻渴望。创伤提示后，与奖赏处理相关的脑区内部或之间的功能连接（FC）改变可能会加强这种联系；然而，潜在的神经机制仍未得到研究。
我们在2021年2月至2022年8月招募了有创伤史的大麻使用者。参与者完成了一次关于个人相关创伤经历、与创伤或压力无关的典型大麻使用情况以及情绪中性情况的半结构化访谈，访谈回答为3分钟视听线索的开发提供了信息。采用随机交叉设计，我们使用适用于磁共振成像（MRI）环境的线索反应范式，以平衡的顺序向参与者呈现中性、大麻相关和创伤相关情况的个性化音频记录和图像。参与者在每次线索呈现后自我报告主观大麻渴望以及积极和消极情绪。我们在每次线索呈现期间通过功能磁共振成像测量纹状体、皮质和边缘区域之间的FC。
我们纳入了27名有创伤史的大麻使用者（74.1%为女性，平均年龄32.2岁，标准差10.5岁）。与其他线索相比，创伤线索增加了大麻渴望和消极情绪，并降低了积极情绪。与中性和基线线索相比，大麻线索增加了渴望。与中性线索相比，创伤线索增加了纹状体内以及纹状体 - 皮质区域之间的FC，与大麻线索相比增加了纹状体 - 皮质FC。与创伤线索相比，大麻线索增加了皮质和皮质 - 边缘FC，与中性线索相比增加了纹状体 - 皮质FC。
样本量较小，且并非仅由患有创伤后应激障碍或大麻使用障碍诊断的参与者组成。
研究结果提示了创伤与大麻使用之间联系的潜在神经机制。与创伤和大麻相关的线索可能通过改变奖赏回路FC来增强大麻渴望。
