Experimental and Clinical Pharmacopsychology, Clinic of Affective Disorders and General Psychiatry, University Hospital of Psychiatry, University of Zurich, Switzerland.
Eur Neuropsychopharmacol. 2013 Oct;23(10):1270-9. doi: 10.1016/j.euroneuro.2012.11.007. Epub 2012 Dec 7.
Models of addiction and addiction memory propose that drug-associated cues elicit incentive effects in drug users, which play an important role in maintenance of drug use and relapse. Incentive effects have been demonstrated for smoking and alcohol-related cues but evidence for heroin-related cues has been inconclusive. Furthermore, it is unknown whether appetitive effects of heroin-related cues persist after prolonged abstinence, although heroin addiction is known to have high relapse rates. Therefore, we investigated implicit and explicit valence of heroin-related cues in dependent users at different stages of abstinence using affective startle modulation. In Study I, 15 current heroin users were measured before and after detoxification. Correspondingly, 15 healthy control participants were tested twice at an interval of 14 days. In Study II, 14 long-term abstinent heroin users were additionally measured in a single session. Implicit processing of drug-related stimuli was assessed using affective startle modulation by pictures of heroin and smoking scenes. Explicit reactions were measured using ratings of valence and craving. In contrast to controls, heroin-dependent participants showed a clear reduction of startle response during heroin-related pictures (p<0.05). Detoxification did not significantly change their startle responses to heroin-cues. No difference between non-detoxified current and long-term abstinent heroin users was found in implicit reactions to heroin-cues, whereas explicit measures differed between both groups (all p<0.05). After detoxification and even after prolonged abstinence, heroin cues still exert implicit appetitive effects in heroin users. This implies that drug-induced adaptations of reward circuits are long-lasting, resulting in a highly stable addiction memory.
成瘾和成瘾记忆模型提出，药物相关线索会在药物使用者中引起激励效应，这在维持药物使用和复发中起着重要作用。已经证明了吸烟和酒精相关线索的激励效应，但关于海洛因相关线索的证据尚无定论。此外，尽管众所周知海洛因成瘾的复发率很高，但尚不清楚海洛因相关线索的快感效应是否会在长时间戒断后持续存在。因此，我们使用情感性惊跳调制来研究不同戒断阶段的依赖使用者对海洛因相关线索的内隐和外显效价。在研究 I 中，15 名当前的海洛因使用者在解毒前后进行了测量。相应地，15 名健康对照参与者在 14 天的间隔内进行了两次测试。在研究 II 中，14 名长期戒断的海洛因使用者还在一次会议中进行了测量。使用海洛因和吸烟场景的图片来评估情感性惊跳调制，评估对药物相关刺激的内隐处理。使用效价和渴望评分来测量外显反应。与对照组相比，海洛因依赖者在海洛因相关图片时表现出明显的惊跳反应减少（p<0.05）。解毒并未显著改变他们对海洛因线索的惊跳反应。在对海洛因线索的内隐反应中，未解毒的当前和长期戒断的海洛因使用者之间没有差异，而两组之间的外显测量则存在差异（均 p<0.05）。在解毒后甚至在长时间戒断后，海洛因线索仍在海洛因使用者中产生内隐的食欲效应。这意味着药物引起的奖励回路的适应性是持久的，导致高度稳定的成瘾记忆。
