Individuals with mood/anxiety disorders may use cannabis for “self-medication,” i.e., to induce positive mood or attenuate aversive mood states. However, little neurobiological evidence supports such use. The goal of this investigation was to test the hypothesis that cannabis use attenuates striatal response to reward in those with mood/anxiety disorders. Reward-related processing was measured using a monetary incentive delay task under functional MRI. Individuals with any lifetime mood/anxiety disorder diagnoses and problematic cannabis use (“Mood/Anxiety+CB”; n = 41) were compared with a propensity score-matched group of similar subjects without cannabis use (“Mood/Anxiety−CB”; n = 41), and a cannabis-naïve healthy control group (n = 35). Activations during win- and loss-anticipations were extracted from bilateral nucleus accumbens, dorsal caudate, and dorsolateral putamen. Mixed models were estimated for each region separately for win- and loss-anticipations, with a test for the main effect of group, condition (e.g., high-win, low-win, neutral), and their interaction. A significant main effect of group for win- and loss-anticipation was observed for each striatal region. Specifically, the Mood/Anxiety+CB group exhibited the lowest striatal activations across condition levels relative to both the Mood/Anxiety-CB and healthy group. A significant group-by-condition interaction was only observed for the dorsolateral putamen and indicated divergent activation modulation as a function of win and loss-magnitude for Mood/Anxiety+CB subjects. Finally, individuals with heavier recent cannabis use showed greater attenuation of gain-related activation in all three striatal regions. There was no such relationship for other illicit drugs. These data support the hypothesis that cannabis use in individuals with mood/anxiety disorders is associated with attenuated brain processing of reward magnitude, which may contribute to persistent affective symptoms.

患有情绪/焦虑症的人可能会使用大麻进行“自我药疗”，即诱导积极情绪或减轻厌恶情绪状态。然而，很少有神经生物学证据支持这种使用。这项调查的目的是验证使用大麻会减弱情绪/焦虑症患者纹状体对奖励的反应的假设。奖励相关处理使用功能性 MRI 下的货币激励延迟任务进行测量。将患有任何终生情绪/焦虑障碍诊断和大麻使用问题（“情绪/焦虑+CB”；n  = 41）的个体与未使用大麻的相似受试者的倾向得分匹配组（“情绪/焦虑-CB”；n  = 41）和一个未使用大麻的健康对照组（n = 35)。从双侧伏隔核、背尾状核和背外侧壳核中提取了赢和输预期期间的激活。混合模型分别为每个区域估计赢和输预期，并测试组、条件（例如，高赢、低赢、中性）及其相互作用的主要影响。对于每个纹状体区域，观察到组对输赢预期的显着主效应。具体来说，相对于情绪/焦虑-CB 组和健康组，情绪/焦虑+CB 组在各种条件水平上表现出最低的纹状体激活。仅在背外侧壳核中观察到显着的逐组条件相互作用，并表明不同的激活调制是情绪/焦虑 + CB 受试者的获胜和损失幅度的函数。最后，最近吸食大麻较多的个体在所有三个纹状体区域显示出与增益相关的激活的更大衰减。其他非法药物没有这种关系。这些数据支持这样的假设，即在患有情绪/焦虑症的个体中使用大麻与奖励幅度的大脑处理减弱有关，这可能导致持续的情感症状。